diff --git a/cmd/staking/root.go b/cmd/staking/root.go
index c5a7bf7ed..053fc106a 100644
--- a/cmd/staking/root.go
+++ b/cmd/staking/root.go
@@ -170,6 +170,21 @@ func (s *staker) run(cmd *cobra.Command, args []string) error {
 	rlp.DecodeBytes(enc, tx)
 	hexSignature := hexutil.Encode(enc)
 	param := []interface{}{hexSignature}
+
+	// Check Double check if have enough balance for gas fees
+	balanceR, _ := baseRequest("hmy_getBalance", "http://localhost:9500", []interface{}{testAccounts[index], "latest"})
+	m := map[string]interface{}{}
+	json.Unmarshal(balanceR, &m)
+	balance, _ := m["result"].(string)
+	bln, _ := big.NewInt(0).SetString(balance[2:], 16)
+
+	if bln.Cmp(big.NewInt(0)) == 0 {
+		fmt.Println("Balance for ", testAccounts[index], "is zero, tx will be rejected b/c not enough for gas fee, exiting")
+		os.Exit(-1)
+	}
+
+	fmt.Println("balance", convertBalanceIntoReadableFormat(bln))
+
 	result, reqOops := baseRequest(stakingRPC, "http://localhost:9500", param)
 	fmt.Println(string(result))
 	return reqOops
@@ -245,3 +260,43 @@ var (
 		},
 	}
 )
+
+func convertBalanceIntoReadableFormat(balance *big.Int) string {
+	balance = balance.Div(balance, big.NewInt(denominations.Nano))
+	strBalance := fmt.Sprintf("%d", balance.Uint64())
+
+	bytes := []byte(strBalance)
+	hasDecimal := false
+	for i := 0; i < 11; i++ {
+		if len(bytes)-1-i < 0 {
+			bytes = append([]byte{'0'}, bytes...)
+		}
+		if bytes[len(bytes)-1-i] != '0' && i < 9 {
+			hasDecimal = true
+		}
+		if i == 9 {
+			newBytes := append([]byte{'.'}, bytes[len(bytes)-i:]...)
+			bytes = append(bytes[:len(bytes)-i], newBytes...)
+		}
+	}
+	zerosToRemove := 0
+	for i := 0; i < len(bytes); i++ {
+		if hasDecimal {
+			if bytes[len(bytes)-1-i] == '0' {
+				bytes = bytes[:len(bytes)-1-i]
+				i--
+			} else {
+				break
+			}
+		} else {
+			if zerosToRemove < 5 {
+				bytes = bytes[:len(bytes)-1-i]
+				i--
+				zerosToRemove++
+			} else {
+				break
+			}
+		}
+	}
+	return string(bytes)
+}
diff --git a/consensus/consensus_service.go b/consensus/consensus_service.go
index eda4e804e..624492934 100644
--- a/consensus/consensus_service.go
+++ b/consensus/consensus_service.go
@@ -460,7 +460,6 @@ func (consensus *Consensus) UpdateConsensusInformation() Mode {
 	curPubKeys := committee.WithStakingEnabled.ComputePublicKeys(
 		epoch, consensus.ChainReader,
 	)[int(header.ShardID())]
-
 	consensus.numPrevPubKeys = len(curPubKeys)
 	consensus.getLogger().Info().Msg("[UpdateConsensusInformation] Updating.....")
 	if shard.Schedule.IsLastBlock(header.Number().Uint64()) {
diff --git a/consensus/engine/consensus_engine.go b/consensus/engine/consensus_engine.go
index 76ff47b97..a2fd2101a 100644
--- a/consensus/engine/consensus_engine.go
+++ b/consensus/engine/consensus_engine.go
@@ -10,6 +10,8 @@ import (
 	"github.com/harmony-one/harmony/core/types"
 	"github.com/harmony-one/harmony/internal/params"
 	"github.com/harmony-one/harmony/shard"
+	"github.com/harmony-one/harmony/shard/committee"
+	"github.com/harmony-one/harmony/staking/slash"
 	staking "github.com/harmony-one/harmony/staking/types"
 )
 
@@ -42,6 +44,9 @@ type ChainReader interface {
 
 	// ReadActiveValidatorList retrieves the list of active validators
 	ReadActiveValidatorList() ([]common.Address, error)
+
+	// Methods needed for EPoS committee assignment calculation
+	committee.StakingCandidatesReader
 }
 
 // Engine is an algorithm agnostic consensus engine.
@@ -83,6 +88,12 @@ type Engine interface {
 	// SetRewarder assigns the Distributor used in block reward
 	SetRewarder(reward.Distributor)
 
+	// Slasher handles slashing accounts due to inavailibility or double-signing
+	Slasher() slash.Slasher
+
+	// SetSlasher assigns the slasher used
+	SetSlasher(slash.Slasher)
+
 	// Finalize runs any post-transaction state modifications (e.g. block rewards)
 	// and assembles the final block.
 	// Note: The block header and state database might be updated to reflect any
diff --git a/consensus/quorum/one-node-one-vote.go b/consensus/quorum/one-node-one-vote.go
index 8595a9c31..0c065a16e 100644
--- a/consensus/quorum/one-node-one-vote.go
+++ b/consensus/quorum/one-node-one-vote.go
@@ -1,17 +1,20 @@
 package quorum
 
 import (
+	"encoding/json"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/harmony-one/bls/ffi/go/bls"
 	"github.com/harmony-one/harmony/internal/utils"
+	"github.com/harmony-one/harmony/shard"
 	// "github.com/harmony-one/harmony/staking/effective"
 )
 
 type uniformVoteWeight struct {
-	SignatureReader
 	DependencyInjectionWriter
+	DependencyInjectionReader
+	SignatureReader
 }
 
 // Policy ..
@@ -40,9 +43,9 @@ func (v *uniformVoteWeight) IsRewardThresholdAchieved() bool {
 	return v.SignersCount(Commit) >= (v.ParticipantsCount() * 9 / 10)
 }
 
-// func (v *uniformVoteWeight) UpdateVotingPower(effective.StakeKeeper) {
-// NO-OP do not add anything here
-// }
+func (v *uniformVoteWeight) UpdateVotingPower(shard.SlotList) {
+	// NO-OP do not add anything here
+}
 
 // ToggleActive for uniform vote is a no-op, always says that voter is active
 func (v *uniformVoteWeight) ToggleActive(*bls.PublicKey) bool {
@@ -71,3 +74,23 @@ func (v *uniformVoteWeight) Award(
 
 	return payout
 }
+
+func (v *uniformVoteWeight) ShouldSlash(k shard.BlsPublicKey) bool {
+	// No-op, no semantic meaning in one-slot-one-vote
+	return false
+}
+
+func (v *uniformVoteWeight) JSON() string {
+	s, _ := v.ShardIDProvider()()
+
+	type t struct {
+		Policy       string   `json"policy"`
+		ShardID      uint32   `json:"shard-id"`
+		Count        int      `json:"count"`
+		Participants []string `json:"committee-members"`
+	}
+
+	members := v.DumpParticipants()
+	b1, _ := json.Marshal(t{v.Policy().String(), s, len(members), members})
+	return string(b1)
+}
diff --git a/consensus/quorum/one-node-staked-vote.go b/consensus/quorum/one-node-staked-vote.go
index efd2b385b..074f25e89 100644
--- a/consensus/quorum/one-node-staked-vote.go
+++ b/consensus/quorum/one-node-staked-vote.go
@@ -1,29 +1,35 @@
 package quorum
 
 import (
+	"encoding/json"
 	"math/big"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/harmony-one/bls/ffi/go/bls"
+	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/numeric"
 	"github.com/harmony-one/harmony/shard"
+	"github.com/harmony-one/harmony/staking/slash"
 )
 
 var (
-	twoThirds = numeric.NewDec(2).QuoInt64(3).Int
+	twoThirds = numeric.NewDec(2).QuoInt64(3)
+	hSentinel = numeric.ZeroDec()
 )
 
 type stakedVoter struct {
 	isActive, isHarmonyNode bool
+	earningAccount          common.Address
 	effective               numeric.Dec
 }
 
 type stakedVoteWeight struct {
 	SignatureReader
 	DependencyInjectionWriter
-	// EPOS based staking
-	validatorStakes            map[[shard.PublicKeySizeInBytes]byte]stakedVoter
-	totalEffectiveStakedAmount *big.Int
+	DependencyInjectionReader
+	slash.ThresholdDecider
+	validatorStakes map[shard.BlsPublicKey]stakedVoter
+	total           numeric.Dec
 }
 
 // Policy ..
@@ -31,45 +37,141 @@ func (v *stakedVoteWeight) Policy() Policy {
 	return SuperMajorityStake
 }
 
-// We must maintain 2/3 quoroum, so whatever is 2/3 staked amount,
-// we divide that out & you
 // IsQuorumAchieved ..
 func (v *stakedVoteWeight) IsQuorumAchieved(p Phase) bool {
-	// TODO Implement this logic
+	// TODO Implement this logic w/Chao
+	// soFar := numeric.ZeroDec()
+	w := shard.BlsPublicKey{}
+	members := v.Participants()
+
+	for i := range members {
+		w.FromLibBLSPublicKey(members[i])
+		// isHMY := v.validatorStakes[w].isHarmonyNode
+		if v.ReadSignature(p, members[i]) == nil {
+			// TODO TODO finish this logic
+		}
+	}
+
 	return true
 }
 
 // QuorumThreshold ..
 func (v *stakedVoteWeight) QuorumThreshold() *big.Int {
-	return new(big.Int).Mul(v.totalEffectiveStakedAmount, twoThirds)
+	return v.total.Mul(twoThirds).Ceil().RoundInt()
 }
 
 // RewardThreshold ..
 func (v *stakedVoteWeight) IsRewardThresholdAchieved() bool {
 	// TODO Implement
-	return false
+	return true
 }
 
-// HACK
-var (
-	hSentinel          = big.NewInt(0)
-	hEffectiveSentinel = numeric.ZeroDec()
-)
-
 // Award ..
 func (v *stakedVoteWeight) Award(
 	Pie *big.Int, earners []common.Address, hook func(earner common.Address, due *big.Int),
 ) *big.Int {
-	// TODO Implement
-	return nil
+	payout := big.NewInt(0)
+	last := big.NewInt(0)
+	count := big.NewInt(int64(len(earners)))
+	proportional := map[common.Address]numeric.Dec{}
+
+	for _, details := range v.validatorStakes {
+		if details.isHarmonyNode == false {
+			proportional[details.earningAccount] = details.effective.QuoTruncate(
+				v.total,
+			)
+		}
+	}
+	// TODO Finish implementing this logic w/Chao
+
+	for i := range earners {
+		cur := big.NewInt(0)
+
+		cur.Mul(Pie, big.NewInt(int64(i+1))).Div(cur, count)
+
+		diff := big.NewInt(0).Sub(cur, last)
+
+		// hook(common.Address(account), diff)
+
+		payout = big.NewInt(0).Add(payout, diff)
+
+		last = cur
+	}
+
+	return payout
 }
 
-// UpdateVotingPower called only at epoch change, prob need to move to CalculateShardState
-// func (v *stakedVoteWeight) UpdateVotingPower(keeper effective.StakeKeeper) {
-// TODO Implement
-// }
+func (v *stakedVoteWeight) UpdateVotingPower(staked shard.SlotList) {
+	s, _ := v.ShardIDProvider()()
 
-func (v *stakedVoteWeight) ToggleActive(*bls.PublicKey) bool {
-	// TODO Implement
-	return true
+	v.validatorStakes = map[shard.BlsPublicKey]stakedVoter{}
+	v.Reset([]Phase{Prepare, Commit, ViewChange})
+
+	for i := range staked {
+		if staked[i].StakeWithDelegationApplied != nil {
+			v.validatorStakes[staked[i].BlsPublicKey] = stakedVoter{
+				true, false, staked[i].EcdsaAddress, *staked[i].StakeWithDelegationApplied,
+			}
+			v.total = v.total.Add(*staked[i].StakeWithDelegationApplied)
+		} else {
+			v.validatorStakes[staked[i].BlsPublicKey] = stakedVoter{
+				true, true, staked[i].EcdsaAddress, hSentinel,
+			}
+		}
+	}
+
+	utils.Logger().Info().
+		Uint32("on-shard", s).
+		Str("Staked", v.total.String()).
+		Msg("Total staked")
+}
+
+func (v *stakedVoteWeight) ToggleActive(k *bls.PublicKey) bool {
+	w := shard.BlsPublicKey{}
+	w.FromLibBLSPublicKey(k)
+	g := v.validatorStakes[w]
+	g.isActive = !g.isActive
+	v.validatorStakes[w] = g
+	return v.validatorStakes[w].isActive
+}
+
+func (v *stakedVoteWeight) ShouldSlash(key shard.BlsPublicKey) bool {
+	s, _ := v.ShardIDProvider()()
+	switch s {
+	case shard.BeaconChainShardID:
+		return v.SlashThresholdMet(key)
+	default:
+		return false
+	}
+}
+
+func (v *stakedVoteWeight) JSON() string {
+	s, _ := v.ShardIDProvider()()
+
+	type t struct {
+		Policy       string   `json"policy"`
+		ShardID      uint32   `json:"shard-id"`
+		Count        int      `json:"count"`
+		Participants []string `json:"committee-members"`
+		TotalStaked  string   `json:"total-staked"`
+	}
+
+	members := v.DumpParticipants()
+	parts := []string{}
+	for i := range members {
+		k := bls.PublicKey{}
+		k.DeserializeHexStr(members[i])
+		w := shard.BlsPublicKey{}
+		w.FromLibBLSPublicKey(&k)
+		staker := v.validatorStakes[w]
+		if staker.isHarmonyNode {
+			parts = append(parts, members[i])
+		} else {
+			parts = append(parts, members[i]+"-"+staker.effective.String())
+		}
+	}
+	b1, _ := json.Marshal(t{
+		v.Policy().String(), s, len(members), parts, v.total.String(),
+	})
+	return string(b1)
 }
diff --git a/consensus/quorum/quorum.go b/consensus/quorum/quorum.go
index 61d91cfc6..af2633119 100644
--- a/consensus/quorum/quorum.go
+++ b/consensus/quorum/quorum.go
@@ -5,7 +5,9 @@ import (
 	"math/big"
 
 	"github.com/harmony-one/bls/ffi/go/bls"
+	"github.com/harmony-one/harmony/numeric"
 	"github.com/harmony-one/harmony/shard"
+	"github.com/harmony-one/harmony/staking/slash"
 	// "github.com/harmony-one/harmony/staking/effective"
 )
 
@@ -44,6 +46,19 @@ const (
 	SuperMajorityStake
 )
 
+var policyNames = map[Policy]string{
+	SuperMajorityStake: "SuperMajorityStake",
+	SuperMajorityVote:  "SuperMajorityVote",
+}
+
+func (p Policy) String() string {
+	if name, ok := policyNames[p]; ok {
+		return name
+	}
+	return fmt.Sprintf("Unknown Quorum Policy %+v", byte(p))
+
+}
+
 // ParticipantTracker ..
 type ParticipantTracker interface {
 	Participants() []*bls.PublicKey
@@ -75,12 +90,24 @@ type DependencyInjectionWriter interface {
 	SetShardIDProvider(func() (uint32, error))
 }
 
+// DependencyInjectionReader ..
+type DependencyInjectionReader interface {
+	ShardIDProvider() func() (uint32, error)
+}
+
+//WithJSONDump representation dump
+type WithJSONDump interface {
+	JSON() string
+}
+
 // Decider ..
 type Decider interface {
 	SignatureReader
 	DependencyInjectionWriter
+	slash.Slasher
+	WithJSONDump
 	ToggleActive(*bls.PublicKey) bool
-	// UpdateVotingPower(keeper effective.StakeKeeper)
+	UpdateVotingPower(shard.SlotList)
 	Policy() Policy
 	IsQuorumAchieved(Phase) bool
 	QuorumThreshold() *big.Int
@@ -96,17 +123,14 @@ type cIdentities struct {
 	commit     map[string]*bls.Sign
 	// viewIDSigs: every validator
 	// sign on |viewID|blockHash| in view changing message
-	viewID map[string]*bls.Sign
+	viewID      map[string]*bls.Sign
+	seenCounter map[[shard.PublicKeySizeInBytes]byte]int
 }
 
 type depInject struct {
 	shardIDProvider func() (uint32, error)
 }
 
-func (d *depInject) SetShardIDProvider(p func() (uint32, error)) {
-	d.shardIDProvider = p
-}
-
 func (s *cIdentities) IndexOf(pubKey *bls.PublicKey) int {
 	idx := -1
 	for k, v := range s.publicKeys {
@@ -132,12 +156,24 @@ func (s *cIdentities) Participants() []*bls.PublicKey {
 }
 
 func (s *cIdentities) UpdateParticipants(pubKeys []*bls.PublicKey) {
+	// TODO - might need to put reset of seen counter in separate method
+	s.seenCounter = make(map[[shard.PublicKeySizeInBytes]byte]int, len(pubKeys))
+	for i := range pubKeys {
+		k := shard.BlsPublicKey{}
+		k.FromLibBLSPublicKey(pubKeys[i])
+		s.seenCounter[k] = 0
+	}
 	s.publicKeys = append(pubKeys[:0:0], pubKeys...)
 }
 
+func (s *cIdentities) SlashThresholdMet(key shard.BlsPublicKey) bool {
+	s.seenCounter[key]++
+	return s.seenCounter[key] == slash.UnavailabilityInConsecutiveBlockSigning
+}
+
 func (s *cIdentities) DumpParticipants() []string {
 	keys := make([]string, len(s.publicKeys))
-	for i := 0; i < len(s.publicKeys); i++ {
+	for i := range s.publicKeys {
 		keys[i] = s.publicKeys[i].SerializeToHexStr()
 	}
 	return keys
@@ -174,8 +210,8 @@ func (s *cIdentities) AddSignature(p Phase, PubKey *bls.PublicKey, sig *bls.Sign
 }
 
 func (s *cIdentities) Reset(ps []Phase) {
-	for _, p := range ps {
-		switch m := map[string]*bls.Sign{}; p {
+	for i := range ps {
+		switch m := map[string]*bls.Sign{}; ps[i] {
 		case Prepare:
 			s.prepare = m
 		case Commit:
@@ -223,26 +259,46 @@ func (s *cIdentities) ReadAllSignatures(p Phase) []*bls.Sign {
 	return sigs
 }
 
-func newMapBackedSignatureReader() SignatureReader {
+func newMapBackedSignatureReader() *cIdentities {
 	return &cIdentities{
 		[]*bls.PublicKey{}, map[string]*bls.Sign{},
 		map[string]*bls.Sign{}, map[string]*bls.Sign{},
+		map[[shard.PublicKeySizeInBytes]byte]int{},
 	}
 }
 
+type composite struct {
+	DependencyInjectionWriter
+	DependencyInjectionReader
+	SignatureReader
+}
+
+func (d *depInject) SetShardIDProvider(p func() (uint32, error)) {
+	d.shardIDProvider = p
+}
+
+func (d *depInject) ShardIDProvider() func() (uint32, error) {
+	return d.shardIDProvider
+}
+
 // NewDecider ..
 func NewDecider(p Policy) Decider {
 	signatureStore := newMapBackedSignatureReader()
-	dependencies := &depInject{}
+	deps := &depInject{}
+	c := &composite{deps, deps, signatureStore}
 	switch p {
 	case SuperMajorityVote:
-		return &uniformVoteWeight{signatureStore, dependencies}
+		return &uniformVoteWeight{
+			c.DependencyInjectionWriter, c.DependencyInjectionReader, c,
+		}
 	case SuperMajorityStake:
 		return &stakedVoteWeight{
-			signatureStore,
-			dependencies,
-			map[[shard.PublicKeySizeInBytes]byte]stakedVoter{},
-			big.NewInt(0),
+			c.SignatureReader,
+			c.DependencyInjectionWriter,
+			c.DependencyInjectionWriter.(DependencyInjectionReader),
+			c.SignatureReader.(slash.ThresholdDecider),
+			map[shard.BlsPublicKey]stakedVoter{},
+			numeric.ZeroDec(),
 		}
 	default:
 		// Should not be possible
diff --git a/core/chain_makers.go b/core/chain_makers.go
index cdd30e907..8d7da2610 100644
--- a/core/chain_makers.go
+++ b/core/chain_makers.go
@@ -271,3 +271,9 @@ func (cr *fakeChainReader) GetHeader(hash common.Hash, number uint64) *block.Hea
 func (cr *fakeChainReader) GetBlock(hash common.Hash, number uint64) *types.Block   { return nil }
 func (cr *fakeChainReader) ReadShardState(epoch *big.Int) (shard.State, error)      { return nil, nil }
 func (cr *fakeChainReader) ReadActiveValidatorList() ([]common.Address, error)      { return nil, nil }
+
+func (cr *fakeChainReader) ValidatorCandidates() []common.Address { return nil }
+func (cr *fakeChainReader) ReadValidatorData(addr common.Address) (*staking.ValidatorWrapper, error) {
+	return nil, nil
+}
+func (cr *fakeChainReader) ValidatorStakingWithDelegation(addr common.Address) *big.Int { return nil }
diff --git a/core/state_transition.go b/core/state_transition.go
index 9cf9a80d2..204007d7c 100644
--- a/core/state_transition.go
+++ b/core/state_transition.go
@@ -285,6 +285,9 @@ func (st *StateTransition) StakingTransitionDb() (usedGas uint64, err error) {
 	// Pay intrinsic gas
 	// TODO: propose staking-specific formula for staking transaction
 	gas, err := IntrinsicGas(st.data, false, homestead)
+	// TODO Remove this logging
+	utils.Logger().Info().Uint64("Using", gas).Msg("Gas cost of staking transaction being processed")
+
 	if err != nil {
 		return 0, err
 	}
diff --git a/internal/chain/engine.go b/internal/chain/engine.go
index 88f12f375..628843e53 100644
--- a/internal/chain/engine.go
+++ b/internal/chain/engine.go
@@ -11,10 +11,12 @@ import (
 	"github.com/harmony-one/harmony/consensus/reward"
 	"github.com/harmony-one/harmony/core/state"
 	"github.com/harmony-one/harmony/core/types"
+	common2 "github.com/harmony-one/harmony/internal/common"
 	"github.com/harmony-one/harmony/internal/ctxerror"
 	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/shard"
 	"github.com/harmony-one/harmony/shard/committee"
+	"github.com/harmony-one/harmony/staking/slash"
 	staking "github.com/harmony-one/harmony/staking/types"
 	"github.com/pkg/errors"
 	"golang.org/x/crypto/sha3"
@@ -22,10 +24,11 @@ import (
 
 type engineImpl struct {
 	d reward.Distributor
+	s slash.Slasher
 }
 
 // Engine is an algorithm-agnostic consensus engine.
-var Engine = &engineImpl{nil}
+var Engine = &engineImpl{nil, nil}
 
 // Rewarder handles the distribution of block rewards
 func (e *engineImpl) Rewarder() reward.Distributor {
@@ -37,6 +40,16 @@ func (e *engineImpl) SetRewarder(d reward.Distributor) {
 	e.d = d
 }
 
+// Slasher handles slashing accounts due to inavailibility or double-signing
+func (e *engineImpl) Slasher() slash.Slasher {
+	return e.s
+}
+
+// SetSlasher assigns the slasher used
+func (e *engineImpl) SetSlasher(s slash.Slasher) {
+	e.s = s
+}
+
 // SealHash returns the hash of a block prior to it being sealed.
 func (e *engineImpl) SealHash(header *block.Header) (hash common.Hash) {
 	hasher := sha3.NewLegacyKeccak256()
@@ -164,13 +177,16 @@ func (e *engineImpl) VerifySeal(chain engine.ChainReader, header *block.Header)
 // Finalize implements Engine, accumulating the block rewards,
 // setting the final state and assembling the block.
 func (e *engineImpl) Finalize(
-	chain engine.ChainReader, header *block.Header, state *state.DB, txs []*types.Transaction,
+	chain engine.ChainReader, header *block.Header,
+	state *state.DB, txs []*types.Transaction,
 	receipts []*types.Receipt, outcxs []*types.CXReceipt,
-	incxs []*types.CXReceiptsProof, stks []*staking.StakingTransaction) (*types.Block, error) {
+	incxs []*types.CXReceiptsProof, stks []*staking.StakingTransaction,
+) (*types.Block, error) {
 	// Accumulate any block and uncle rewards and commit the final state root
 	// Header seems complete, assemble into a block and return
-	// TODO: Block rewards should be done only in beacon chain based on cross-links
-	if err := AccumulateRewards(chain, state, header, e.Rewarder()); err != nil {
+	if err := AccumulateRewards(
+		chain, state, header, e.Rewarder(), e.Slasher(),
+	); err != nil {
 		return nil, ctxerror.New("cannot pay block reward").WithCause(err)
 	}
 
@@ -194,6 +210,7 @@ func (e *engineImpl) Finalize(
 					return nil, ctxerror.New("failed update validator info").WithCause(err)
 				}
 			} else {
+				err = errors.New("validator came back empty" + common2.MustAddressToBech32(validator))
 				return nil, ctxerror.New("failed getting validator info").WithCause(err)
 			}
 		}
@@ -203,10 +220,12 @@ func (e *engineImpl) Finalize(
 }
 
 // QuorumForBlock returns the quorum for the given block header.
-func QuorumForBlock(chain engine.ChainReader, h *block.Header, reCalculate bool) (quorum int, err error) {
+func QuorumForBlock(
+	chain engine.ChainReader, h *block.Header, reCalculate bool,
+) (quorum int, err error) {
 	var ss shard.State
 	if reCalculate {
-		ss, _ = committee.WithStakingEnabled.Compute(h.Epoch(), *chain.Config(), nil)
+		ss, _ = committee.WithStakingEnabled.Compute(h.Epoch(), *chain.Config(), chain)
 	} else {
 		ss, err = chain.ReadShardState(h.Epoch())
 		if err != nil {
@@ -265,7 +284,7 @@ func GetPublicKeys(chain engine.ChainReader, header *block.Header, reCalculate b
 	var shardState shard.State
 	var err error
 	if reCalculate {
-		shardState, _ = committee.WithStakingEnabled.Compute(header.Epoch(), *chain.Config(), nil)
+		shardState, _ = committee.WithStakingEnabled.Compute(header.Epoch(), *chain.Config(), chain)
 	} else {
 		shardState, err = chain.ReadShardState(header.Epoch())
 		if err != nil {
diff --git a/internal/chain/reward.go b/internal/chain/reward.go
index a6a9e952f..34a5738cc 100644
--- a/internal/chain/reward.go
+++ b/internal/chain/reward.go
@@ -2,6 +2,7 @@ package chain
 
 import (
 	"math/big"
+	"sync"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/harmony-one/bls/ffi/go/bls"
@@ -14,6 +15,8 @@ import (
 	common2 "github.com/harmony-one/harmony/internal/common"
 	"github.com/harmony-one/harmony/internal/ctxerror"
 	"github.com/harmony-one/harmony/internal/utils"
+	"github.com/harmony-one/harmony/shard"
+	"github.com/harmony-one/harmony/staking/slash"
 	"github.com/pkg/errors"
 )
 
@@ -27,7 +30,9 @@ var (
 // reward. The total reward consists of the static block reward and rewards for
 // included uncles. The coinbase of each uncle block is also rewarded.
 func AccumulateRewards(
-	bc engine.ChainReader, state *state.DB, header *block.Header, rewarder reward.Distributor,
+	bc engine.ChainReader, state *state.DB,
+	header *block.Header, rewarder reward.Distributor,
+	slasher slash.Slasher,
 ) error {
 	blockNum := header.Number().Uint64()
 	if blockNum == 0 {
@@ -79,29 +84,54 @@ func AccumulateRewards(
 	}
 
 	accounts := []common.Address{}
+	missing := shard.SlotList{}
 
 	for idx, member := range parentCommittee.Slots {
-		if signed, err := mask.IndexEnabled(idx); err != nil {
+		switch signed, err := mask.IndexEnabled(idx); true {
+		case err != nil:
 			return ctxerror.New("cannot check for committer bit",
 				"committerIndex", idx,
 			).WithCause(err)
-		} else if signed {
+		case signed:
 			accounts = append(accounts, member.EcdsaAddress)
+		default:
+			missing = append(missing, member)
 		}
 	}
 
-	type t struct {
+	// do it quickly
+	w := sync.WaitGroup{}
+	for i := range missing {
+		w.Add(1)
+		go func(member int) {
+			defer w.Done()
+			// Slash if missing block was long enough
+			if slasher.ShouldSlash(missing[member].BlsPublicKey) {
+				// TODO Logic
+			}
+		}(i)
+	}
+
+	w.Wait()
+
+	payable := []struct {
+		string
 		common.Address
 		*big.Int
-	}
-	signers := []string{}
-	payable := []t{}
+	}{}
 
 	totalAmount := rewarder.Award(
 		BlockReward, accounts, func(receipient common.Address, amount *big.Int) {
-			signers = append(signers, common2.MustAddressToBech32(receipient))
-			payable = append(payable, t{receipient, amount})
-		})
+			payable = append(payable, struct {
+				string
+				common.Address
+				*big.Int
+			}{
+				common2.MustAddressToBech32(receipient), receipient, amount,
+			},
+			)
+		},
+	)
 
 	if totalAmount.Cmp(BlockReward) != 0 {
 		utils.Logger().Error().
@@ -111,7 +141,10 @@ func AccumulateRewards(
 		return errors.Wrapf(errPayoutNotEqualBlockReward, "payout "+totalAmount.String())
 	}
 
+	signers := make([]string, len(payable))
+
 	for i := range payable {
+		signers[i] = payable[i].string
 		state.AddBalance(payable[i].Address, payable[i].Int)
 	}
 
diff --git a/node/node.go b/node/node.go
index eececed4b..7401e3daf 100644
--- a/node/node.go
+++ b/node/node.go
@@ -33,6 +33,7 @@ import (
 	p2p_host "github.com/harmony-one/harmony/p2p/host"
 	"github.com/harmony-one/harmony/shard"
 	"github.com/harmony-one/harmony/shard/committee"
+	"github.com/harmony-one/harmony/staking/slash"
 	staking "github.com/harmony-one/harmony/staking/types"
 )
 
@@ -372,7 +373,8 @@ func (node *Node) GetSyncID() [SyncIDLength]byte {
 }
 
 // New creates a new node.
-func New(host p2p.Host, consensusObj *consensus.Consensus, chainDBFactory shardchain.DBFactory, isArchival bool) *Node {
+func New(host p2p.Host, consensusObj *consensus.Consensus,
+	chainDBFactory shardchain.DBFactory, isArchival bool) *Node {
 	node := Node{}
 
 	node.syncFreq = SyncFrequency
@@ -431,6 +433,8 @@ func New(host p2p.Host, consensusObj *consensus.Consensus, chainDBFactory shardc
 		node.pendingStakingTransactions = make(map[common.Hash]*staking.StakingTransaction)
 		node.Consensus.VerifiedNewBlock = make(chan *types.Block)
 		chain.Engine.SetRewarder(node.Consensus.Decider.(reward.Distributor))
+		chain.Engine.SetSlasher(node.Consensus.Decider.(slash.Slasher))
+
 		// the sequence number is the next block number to be added in consensus protocol, which is always one more than current chain header block
 		node.Consensus.SetBlockNum(blockchain.CurrentBlock().NumberU64() + 1)
 
diff --git a/node/node_handler.go b/node/node_handler.go
index eb2f2a9cb..cf60f0d34 100644
--- a/node/node_handler.go
+++ b/node/node_handler.go
@@ -8,18 +8,17 @@ import (
 	"sync/atomic"
 	"time"
 
-	bls2 "github.com/harmony-one/harmony/crypto/bls"
-
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/harmony-one/bls/ffi/go/bls"
-	libp2p_peer "github.com/libp2p/go-libp2p-core/peer"
-
 	"github.com/harmony-one/harmony/api/proto"
 	proto_discovery "github.com/harmony-one/harmony/api/proto/discovery"
 	proto_node "github.com/harmony-one/harmony/api/proto/node"
 	"github.com/harmony-one/harmony/block"
+	"github.com/harmony-one/harmony/consensus/quorum"
 	"github.com/harmony-one/harmony/core/types"
+	bls2 "github.com/harmony-one/harmony/crypto/bls"
 	nodeconfig "github.com/harmony-one/harmony/internal/configs/node"
 	"github.com/harmony-one/harmony/internal/ctxerror"
 	"github.com/harmony-one/harmony/internal/utils"
@@ -27,7 +26,9 @@ import (
 	"github.com/harmony-one/harmony/p2p"
 	"github.com/harmony-one/harmony/p2p/host"
 	"github.com/harmony-one/harmony/shard"
+	"github.com/harmony-one/harmony/shard/committee"
 	staking "github.com/harmony-one/harmony/staking/types"
+	libp2p_peer "github.com/libp2p/go-libp2p-core/peer"
 )
 
 const (
@@ -377,10 +378,36 @@ func (node *Node) PostConsensusProcessing(newBlock *types.Block, commitSigAndBit
 			}
 		}
 	}
-
 	// Update consensus keys at last so the change of leader status doesn't mess up normal flow
 	if shard.Schedule.IsLastBlock(newBlock.Number().Uint64()) {
+		next := new(big.Int).Add(newBlock.Epoch(), common.Big1)
+		if node.chainConfig.StakingEpoch.Cmp(next) == 0 &&
+			node.Consensus.Decider.Policy() != quorum.SuperMajorityStake {
+			node.Consensus.Decider = quorum.NewDecider(quorum.SuperMajorityStake)
+			node.Consensus.Decider.SetShardIDProvider(func() (uint32, error) {
+				return node.Consensus.ShardID, nil
+			})
+			s, _ := committee.WithStakingEnabled.Compute(
+				next, node.chainConfig, node.Consensus.ChainReader,
+			)
+			node.Consensus.Decider.UpdateVotingPower(
+				s.FindCommitteeByID(node.Consensus.ShardID).Slots,
+			)
+		}
+		// TODO Need to refactor UpdateConsensusInformation so can fold the following logic
+		// into UCI - todo because UCI mutates state & called in overloaded contexts
 		node.Consensus.UpdateConsensusInformation()
+
+		if shard.Schedule.IsLastBlock(newBlock.Number().Uint64()) {
+			if node.chainConfig.StakingEpoch.Cmp(next) == 0 {
+				// Hit this case again, need after UpdateConsensus
+				curPubKeys := committee.WithStakingEnabled.ComputePublicKeys(
+					next, node.Consensus.ChainReader,
+				)[int(node.Consensus.ShardID)]
+				node.Consensus.Decider.UpdateParticipants(curPubKeys)
+			}
+		}
+
 	}
 
 	// TODO chao: uncomment this after beacon syncing is stable
diff --git a/node/node_newblock.go b/node/node_newblock.go
index c6bcf364a..b8dec7191 100644
--- a/node/node_newblock.go
+++ b/node/node_newblock.go
@@ -120,7 +120,7 @@ func (node *Node) proposeNewBlock() (*types.Block, error) {
 
 	// Prepare shard state
 	shardState, err := node.Worker.SuperCommitteeForNextEpoch(
-		node.Consensus.ShardID, node.Beaconchain(),
+		node.Consensus.ShardID, node.Blockchain(),
 	)
 
 	if err != nil {
@@ -136,6 +136,7 @@ func (node *Node) proposeNewBlock() (*types.Block, error) {
 	return node.Worker.FinalizeNewBlock(sig, mask, node.Consensus.GetViewID(), coinbase, crossLinks, shardState)
 }
 
+// TODO is this still needed?
 func (node *Node) proposeLocalShardState(block *types.Block) {
 	logger := block.Logger(utils.Logger())
 	// TODO ek – read this from beaconchain once BC sync is fixed
diff --git a/shard/committee/assignment.go b/shard/committee/assignment.go
index 545bda336..ee24b58c1 100644
--- a/shard/committee/assignment.go
+++ b/shard/committee/assignment.go
@@ -10,6 +10,7 @@ import (
 	shardingconfig "github.com/harmony-one/harmony/internal/configs/sharding"
 	"github.com/harmony-one/harmony/internal/ctxerror"
 	"github.com/harmony-one/harmony/internal/params"
+	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/shard"
 	"github.com/harmony-one/harmony/staking/effective"
 	staking "github.com/harmony-one/harmony/staking/types"
@@ -119,6 +120,8 @@ func eposStakedCommittee(
 	candidates := stakerReader.ValidatorCandidates()
 	essentials := map[common.Address]effective.SlotOrder{}
 
+	utils.Logger().Info().Int("staked-candidates", len(candidates)).Msg("preparing epos staked committee")
+
 	// TODO benchmark difference if went with data structure that sorts on insert
 	for i := range candidates {
 		// TODO Should be using .ValidatorStakingWithDelegation, not implemented yet
@@ -170,7 +173,11 @@ func eposStakedCommittee(
 			&slot.Dec,
 		})
 	}
-
+	if c := len(candidates); c != 0 {
+		utils.Logger().Info().Int("staked-candidates", c).
+			RawJSON("staked-super-committee", []byte(superComm.JSON())).
+			Msg("EPoS based super-committe")
+	}
 	return superComm, nil
 }
 
diff --git a/shard/shard_state.go b/shard/shard_state.go
index 65644b0b0..b850c2dcc 100644
--- a/shard/shard_state.go
+++ b/shard/shard_state.go
@@ -38,7 +38,7 @@ type BlsPublicKey [PublicKeySizeInBytes]byte
 type Slot struct {
 	EcdsaAddress common.Address `json:"ecdsa-address"`
 	BlsPublicKey BlsPublicKey   `json:"bls-pubkey"`
-	// nil means not active, 0 means our node, >= 0 means staked node
+	// nil means our node, 0 means not active, >= 0 means staked node
 	StakeWithDelegationApplied *numeric.Dec `json:"staked-validator" rlp:"nil"`
 }
 
@@ -55,7 +55,7 @@ type Committee struct {
 func (ss State) JSON() string {
 	type t struct {
 		Slot
-		EcdsaAddress string `json:"one-address"`
+		EcdsaAddress string `json:"ecdsa-address"`
 	}
 	type v struct {
 		Committee
diff --git a/staking/slash/slasher.go b/staking/slash/slasher.go
new file mode 100644
index 000000000..c6e1e4047
--- /dev/null
+++ b/staking/slash/slasher.go
@@ -0,0 +1,19 @@
+package slash
+
+import "github.com/harmony-one/harmony/shard"
+
+const (
+	// UnavailabilityInConsecutiveBlockSigning is how many blocks in a row
+	// before "slashing by unavailability" occurs
+	UnavailabilityInConsecutiveBlockSigning = 1380
+)
+
+// Slasher ..
+type Slasher interface {
+	ShouldSlash(shard.BlsPublicKey) bool
+}
+
+// ThresholdDecider ..
+type ThresholdDecider interface {
+	SlashThresholdMet(shard.BlsPublicKey) bool
+}
diff --git a/staking/types/validator.go b/staking/types/validator.go
index 0a5b4f0d8..c2333060f 100644
--- a/staking/types/validator.go
+++ b/staking/types/validator.go
@@ -11,6 +11,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 	common2 "github.com/harmony-one/harmony/internal/common"
 	"github.com/harmony-one/harmony/internal/ctxerror"
+	"github.com/harmony-one/harmony/internal/utils"
 	"github.com/harmony-one/harmony/numeric"
 	"github.com/harmony-one/harmony/shard"
 )
@@ -56,6 +57,7 @@ type Validator struct {
 	Address common.Address `json:"address" yaml:"address"`
 	// The BLS public key of the validator for consensus
 	SlotPubKeys []shard.BlsPublicKey `json:"slot_pub_keys" yaml:"slot_pub_keys"`
+	// TODO Need to remove this .Stake Field
 	// The stake put by the validator itself
 	Stake *big.Int `json:"stake" yaml:"stake"`
 	// if unbonding, height at which this validator has begun unbonding
@@ -118,6 +120,13 @@ func (w *ValidatorWrapper) SanityCheck() error {
 
 	hundredPercent := numeric.NewDec(1)
 	zeroPercent := numeric.NewDec(0)
+
+	utils.Logger().Info().
+		Str("rate", w.Validator.Rate.String()).
+		Str("max-rate", w.Validator.MaxRate.String()).
+		Str("max-change-rate", w.Validator.MaxChangeRate.String()).
+		Msg("Sanity check on validator commission rates, should all be in [0, 1]")
+
 	if w.Validator.Rate.LT(zeroPercent) || w.Validator.Rate.GT(hundredPercent) {
 		return errInvalidComissionRate
 	}
@@ -227,12 +236,12 @@ func CreateValidatorFromNewMsg(val *CreateValidator, blockNum *big.Int) (*Valida
 	commission := Commission{val.CommissionRates, blockNum}
 	pubKeys := []shard.BlsPublicKey{}
 	pubKeys = append(pubKeys, val.SlotPubKeys...)
-
 	// TODO: a new validator should have a minimum of 1 token as self delegation, and that should be added as a delegation entry here.
 	v := Validator{
 		val.ValidatorAddress, pubKeys,
 		val.Amount, new(big.Int), val.MinSelfDelegation, val.MaxTotalDelegation, false,
-		commission, desc, blockNum}
+		commission, desc, blockNum,
+	}
 	return &v, nil
 }
 
diff --git a/test/deploy.sh b/test/deploy.sh
index 478d322cf..1d47ce1dc 100755
--- a/test/deploy.sh
+++ b/test/deploy.sh
@@ -212,7 +212,7 @@ while IFS='' read -r line || [[ -n "$line" ]]; do
 done < $config
 
 if [ "$DOTEST" == "true" ]; then
-   debug_staking
+   # debug_staking
    echo "waiting for some block rewards"
    sleep 60
    i=1