diff --git a/api/struct.go b/api/struct.go
index 84163742d..e6db41d14 100644
--- a/api/struct.go
+++ b/api/struct.go
@@ -82,7 +82,7 @@ type FullNodeStruct struct {
 		StateMinerPeerID           func(ctx context.Context, m address.Address, ts *types.TipSet) (peer.ID, error)     `perm:"read"`
 		StateMinerProvingPeriodEnd func(ctx context.Context, actor address.Address, ts *types.TipSet) (uint64, error)  `perm:"read"`
 		StateCall                  func(context.Context, *types.Message, *types.TipSet) (*types.MessageReceipt, error) `perm:"read"`
-		StateReplay          func(context.Context, *types.TipSet, cid.Cid) (*ReplayResults, error)               `perm:"read"`
+		StateReplay                func(context.Context, *types.TipSet, cid.Cid) (*ReplayResults, error)               `perm:"read"`
 		StateGetActor              func(context.Context, address.Address, *types.TipSet) (*types.Actor, error)         `perm:"read"`
 		StateReadState             func(context.Context, *types.Actor, *types.TipSet) (*ActorState, error)             `perm:"read"`
 
diff --git a/chain/gen/gen.go b/chain/gen/gen.go
index e4b700196..d7d1bef86 100644
--- a/chain/gen/gen.go
+++ b/chain/gen/gen.go
@@ -360,7 +360,7 @@ type mca struct {
 }
 
 func (mca mca) ChainGetRandomness(ctx context.Context, pts *types.TipSet, ticks []*types.Ticket, lb int) ([]byte, error) {
-	return mca.sm.ChainStore().GetRandomness(ctx, pts, ticks, int64(lb))
+	return mca.sm.ChainStore().GetRandomness(ctx, pts.Cids(), ticks, int64(lb))
 }
 
 func (mca mca) StateMinerPower(ctx context.Context, maddr address.Address, ts *types.TipSet) (api.MinerPower, error) {
diff --git a/chain/gen/mining.go b/chain/gen/mining.go
index 3b34e5d56..af0adccb9 100644
--- a/chain/gen/mining.go
+++ b/chain/gen/mining.go
@@ -27,7 +27,7 @@ func MinerCreateBlock(ctx context.Context, sm *stmgr.StateManager, w *wallet.Wal
 
 	height := parents.Height() + uint64(len(tickets))
 
-	r := vm.NewChainRand(sm.ChainStore(), parents, tickets)
+	r := vm.NewChainRand(sm.ChainStore(), parents.Cids(), parents.Height(), tickets)
 	vmi, err := vm.NewVM(st, height, r, miner, sm.ChainStore())
 	if err != nil {
 		return nil, err
diff --git a/chain/stmgr/call.go b/chain/stmgr/call.go
index ba375a2d6..a2fae8c63 100644
--- a/chain/stmgr/call.go
+++ b/chain/stmgr/call.go
@@ -58,7 +58,7 @@ func (sm *StateManager) Call(ctx context.Context, msg *types.Message, ts *types.
 		return nil, err
 	}
 
-	r := vm.NewChainRand(sm.cs, ts, nil)
+	r := vm.NewChainRand(sm.cs, ts.Cids(), ts.Height(), nil)
 
 	return sm.CallRaw(ctx, msg, state, r, ts.Height())
 }
diff --git a/chain/stmgr/stmgr.go b/chain/stmgr/stmgr.go
index 7fc0d8205..1d1afd846 100644
--- a/chain/stmgr/stmgr.go
+++ b/chain/stmgr/stmgr.go
@@ -77,7 +77,12 @@ func (sm *StateManager) computeTipSetState(ctx context.Context, blks []*types.Bl
 		return cid.Undef, xerrors.Errorf("recursive TipSetState failed: %w", err)
 	}
 
-	r := vm.NewChainRand(sm.cs, blks[0], nil)
+	cids := make([]cid.Cid, len(blks))
+	for i, v := range blks {
+		cids[i] = v.Cid()
+	}
+
+	r := vm.NewChainRand(sm.cs, cids, blks[0].Height, nil)
 
 	vmi, err := vm.NewVM(pstate, blks[0].Height, r, address.Undef, sm.cs)
 	if err != nil {
diff --git a/chain/store/store.go b/chain/store/store.go
index a797524d4..e95ccb2a7 100644
--- a/chain/store/store.go
+++ b/chain/store/store.go
@@ -702,7 +702,7 @@ func (cs *ChainStore) TryFillTipSet(ts *types.TipSet) (*FullTipSet, error) {
 	return NewFullTipSet(out), nil
 }
 
-func (cs *ChainStore) GetRandomness(ctx context.Context, pts *types.TipSet, tickets []*types.Ticket, lb int64) ([]byte, error) {
+func (cs *ChainStore) GetRandomness(ctx context.Context, blks []cid.Cid, tickets []*types.Ticket, lb int64) ([]byte, error) {
 	if lb < 0 {
 		return nil, fmt.Errorf("negative lookback parameters are not valid (got %d)", lb)
 	}
@@ -717,9 +717,8 @@ func (cs *ChainStore) GetRandomness(ctx context.Context, pts *types.TipSet, tick
 
 	nv := lb - lt
 
-	nextCids := pts.Cids()
 	for {
-		nts, err := cs.LoadTipSet(nextCids)
+		nts, err := cs.LoadTipSet(blks)
 		if err != nil {
 			return nil, err
 		}
@@ -748,7 +747,7 @@ func (cs *ChainStore) GetRandomness(ctx context.Context, pts *types.TipSet, tick
 			return rval, nil
 		}
 
-		nextCids = mtb.Parents
+		blks = mtb.Parents
 	}
 }
 
diff --git a/chain/sync.go b/chain/sync.go
index b9de70f4e..1ebb2b9e9 100644
--- a/chain/sync.go
+++ b/chain/sync.go
@@ -422,7 +422,7 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) err
 		return xerrors.Errorf("validating block tickets failed: %w", err)
 	}
 
-	rand, err := syncer.sm.ChainStore().GetRandomness(ctx, baseTs, h.Tickets, build.RandomnessLookback)
+	rand, err := syncer.sm.ChainStore().GetRandomness(ctx, baseTs.Cids(), h.Tickets, build.RandomnessLookback)
 	if err != nil {
 		return xerrors.Errorf("failed to get randomness for verifying election proof: %w", err)
 	}
@@ -440,7 +440,7 @@ func (syncer *Syncer) ValidateBlock(ctx context.Context, b *types.FullBlock) err
 		return xerrors.Errorf("miner created a block but was not a winner")
 	}
 
-	r := vm.NewChainRand(syncer.store, baseTs, h.Tickets)
+	r := vm.NewChainRand(syncer.store, baseTs.Cids(), baseTs.Height(), h.Tickets)
 	vmi, err := vm.NewVM(stateroot, h.Height, r, h.Miner, syncer.store)
 	if err != nil {
 		return xerrors.Errorf("failed to instantiate VM: %w", err)
diff --git a/chain/vm/vm.go b/chain/vm/vm.go
index f5c8a21b1..c83187503 100644
--- a/chain/vm/vm.go
+++ b/chain/vm/vm.go
@@ -318,21 +318,23 @@ type Rand interface {
 
 type chainRand struct {
 	cs      *store.ChainStore
-	pts     *types.TipSet
+	blks    []cid.Cid
+	bh      uint64
 	tickets []*types.Ticket
 }
 
-func NewChainRand(cs *store.ChainStore, pts *types.TipSet, tickets []*types.Ticket) Rand {
+func NewChainRand(cs *store.ChainStore, blks []cid.Cid, bheight uint64, tickets []*types.Ticket) Rand {
 	return &chainRand{
 		cs:      cs,
-		pts:     pts,
+		blks:    blks,
+		bh:      bheight,
 		tickets: tickets,
 	}
 }
 
 func (cr *chainRand) GetRandomness(ctx context.Context, h int64) ([]byte, error) {
-	lb := (int64(cr.pts.Height()) + int64(len(cr.tickets))) - h
-	return cr.cs.GetRandomness(ctx, cr.pts, cr.tickets, lb)
+	lb := (int64(cr.bh) + int64(len(cr.tickets))) - h
+	return cr.cs.GetRandomness(ctx, cr.blks, cr.tickets, lb)
 }
 
 type ApplyRet struct {
diff --git a/node/impl/full/chain.go b/node/impl/full/chain.go
index a9e0482c5..51de87165 100644
--- a/node/impl/full/chain.go
+++ b/node/impl/full/chain.go
@@ -45,7 +45,7 @@ func (a *ChainAPI) ChainHead(context.Context) (*types.TipSet, error) {
 }
 
 func (a *ChainAPI) ChainGetRandomness(ctx context.Context, pts *types.TipSet, tickets []*types.Ticket, lb int) ([]byte, error) {
-	return a.Chain.GetRandomness(ctx, pts, tickets, int64(lb))
+	return a.Chain.GetRandomness(ctx, pts.Cids(), tickets, int64(lb))
 }
 
 func (a *ChainAPI) ChainWaitMsg(ctx context.Context, msg cid.Cid) (*api.MsgWait, error) {