diff --git a/beacon_chain/genesis/src/beacon_block.rs b/beacon_chain/genesis/src/beacon_block.rs
index 6caa0c80c6..3d0b8f5126 100644
--- a/beacon_chain/genesis/src/beacon_block.rs
+++ b/beacon_chain/genesis/src/beacon_block.rs
@@ -1,17 +1,15 @@
-use bls::{Signature, BLS_AGG_SIG_BYTE_SIZE};
 use spec::ChainSpec;
-use ssz::{encode::encode_length, Decodable, LENGTH_BYTES};
 use types::{BeaconBlock, BeaconBlockBody, Hash256};
 
 /// Generate a genesis BeaconBlock.
 pub fn genesis_beacon_block(state_root: Hash256, spec: &ChainSpec) -> BeaconBlock {
     BeaconBlock {
-        slot: spec.initial_slot_number,
+        slot: spec.genesis_slot_number,
         parent_root: spec.zero_hash,
         state_root,
         randao_reveal: spec.zero_hash,
         candidate_pow_receipt_root: spec.zero_hash,
-        signature: genesis_signature(),
+        signature: spec.empty_signature.clone(),
         body: BeaconBlockBody {
             proposer_slashings: vec![],
             casper_slashings: vec![],
@@ -25,19 +23,11 @@ pub fn genesis_beacon_block(state_root: Hash256, spec: &ChainSpec) -> BeaconBloc
     }
 }
 
-fn genesis_signature() -> Signature {
-    let mut bytes = encode_length(BLS_AGG_SIG_BYTE_SIZE, LENGTH_BYTES);
-    bytes.append(&mut vec![0; BLS_AGG_SIG_BYTE_SIZE]);
-    let (signature, _) = match Signature::ssz_decode(&bytes, 0) {
-        Ok(sig) => sig,
-        Err(_) => unreachable!(),
-    };
-    signature
-}
 
 #[cfg(test)]
 mod tests {
     use super::*;
+    use bls::{Signature};
 
     #[test]
     fn test_genesis() {
@@ -101,5 +91,6 @@ mod tests {
         for item in raw_sig_bytes.iter() {
             assert!(*item == 0);
         }
+        assert_eq!(genesis_block.signature, Signature::empty_sig());
     }
 }
diff --git a/beacon_chain/genesis/src/beacon_state.rs b/beacon_chain/genesis/src/beacon_state.rs
index 7326bbf1d3..09404275da 100644
--- a/beacon_chain/genesis/src/beacon_state.rs
+++ b/beacon_chain/genesis/src/beacon_state.rs
@@ -21,7 +21,7 @@ pub fn genesis_beacon_state(spec: &ChainSpec) -> Result<BeaconState, Error> {
     };
 
     let initial_crosslink = CrosslinkRecord {
-        slot: spec.initial_slot_number,
+        slot: spec.genesis_slot_number,
         shard_block_root: spec.zero_hash,
     };
 
@@ -29,19 +29,19 @@ pub fn genesis_beacon_state(spec: &ChainSpec) -> Result<BeaconState, Error> {
         /*
          * Misc
          */
-        slot: spec.initial_slot_number,
+        slot: spec.genesis_slot_number,
         genesis_time: spec.genesis_time,
         fork_data: ForkData {
-            pre_fork_version: spec.initial_fork_version,
-            post_fork_version: spec.initial_fork_version,
-            fork_slot: spec.initial_slot_number,
+            pre_fork_version: spec.genesis_fork_version,
+            post_fork_version: spec.genesis_fork_version,
+            fork_slot: spec.genesis_slot_number,
         },
         /*
          * Validator registry
          */
         validator_registry: spec.initial_validators.clone(),
         validator_balances: spec.initial_balances.clone(),
-        validator_registry_latest_change_slot: spec.initial_slot_number,
+        validator_registry_latest_change_slot: spec.genesis_slot_number,
         validator_registry_exit_count: 0,
         validator_registry_delta_chain_tip: spec.zero_hash,
         /*
@@ -52,7 +52,12 @@ pub fn genesis_beacon_state(spec: &ChainSpec) -> Result<BeaconState, Error> {
             spec.zero_hash;
             (spec.latest_randao_mixes_length / spec.epoch_length) as usize
         ],
-        shard_committees_at_slots: vec![],
+        previous_epoch_start_shard: spec.genesis_start_shard,
+        current_epoch_start_shard: spec.genesis_start_shard,
+        previous_epoch_calculation_slot: spec.genesis_slot_number,
+        current_epoch_calculation_slot: spec.genesis_slot_number,
+        previous_epoch_randao_mix: spec.zero_hash,
+        current_epoch_randao_mix: spec.zero_hash,
         /*
          * Custody challenges
          */
@@ -60,10 +65,10 @@ pub fn genesis_beacon_state(spec: &ChainSpec) -> Result<BeaconState, Error> {
         /*
          * Finality
          */
-        previous_justified_slot: spec.initial_slot_number,
-        justified_slot: spec.initial_slot_number,
+        previous_justified_slot: spec.genesis_slot_number,
+        justified_slot: spec.genesis_slot_number,
         justification_bitfield: 0,
-        finalized_slot: spec.initial_slot_number,
+        finalized_slot: spec.genesis_slot_number,
         /*
          * Recent state
          */
diff --git a/beacon_chain/spec/src/foundation.rs b/beacon_chain/spec/src/foundation.rs
index 8e3146ed2b..c622bd4a0e 100644
--- a/beacon_chain/spec/src/foundation.rs
+++ b/beacon_chain/spec/src/foundation.rs
@@ -1,5 +1,5 @@
 use super::ChainSpec;
-use bls::{Keypair, PublicKey, SecretKey};
+use bls::{Keypair, PublicKey, SecretKey, Signature};
 
 use types::{Address, Hash256, ValidatorRecord};
 
@@ -17,12 +17,11 @@ impl ChainSpec {
              * Misc
              */
             shard_count: 1_024,
-            target_committee_size: 256,
+            target_committee_size: 128,
             ejection_balance: 16,
             max_balance_churn_quotient: 32,
             gwei_per_eth: u64::pow(10, 9),
             beacon_chain_shard_number: u64::max_value(),
-            bls_withdrawal_prefix_byte: 0x00,
             max_casper_votes: 1_024,
             latest_block_roots_length: 8_192,
             latest_randao_mixes_length: 8_192,
@@ -38,35 +37,58 @@ impl ChainSpec {
             /*
              * Initial Values
              */
-            initial_fork_version: 0,
-            initial_slot_number: 0,
+            genesis_fork_version: 0,
+            genesis_slot_number: 0,
+            genesis_start_shard: 0,
+            far_future_slot: u64::max_value(),
             zero_hash: Hash256::zero(),
+            empty_signature: Signature::empty_sig(),
+            bls_withdrawal_prefix_byte: 0x00,
             /*
              * Time parameters
              */
             slot_duration: 6,
             min_attestation_inclusion_delay: 4,
             epoch_length: 64,
+            seed_lookahead: 64,
             min_validator_registry_change_interval: 256,
             pow_receipt_root_voting_period: 1_024,
-            shard_persistent_committee_change_period: u64::pow(2, 17),
-            collective_penalty_calculation_period: u64::pow(2, 20),
-            zero_balance_validator_ttl: u64::pow(2, 22),
+            min_validator_withdrawal_time: u64::pow(2, 14),
+            shard_persistent_committee_change_period: u64::pow(2, 17), // old
+            collective_penalty_calculation_period: u64::pow(2, 20),    // old
+            zero_balance_validator_ttl: u64::pow(2, 22),               // old
             /*
              * Reward and penalty quotients
              */
-            base_reward_quotient: 2_048,
+            base_reward_quotient: 1_024,
             whistleblower_reward_quotient: 512,
             includer_reward_quotient: 8,
-            inactivity_penalty_quotient: u64::pow(2, 34),
+            inactivity_penalty_quotient: u64::pow(2, 24),
+            /*
+             * Status flags
+             */
+            initiated_exit: 1,
+            withdrawable: 2,
             /*
              * Max operations per block
              */
             max_proposer_slashings: 16,
-            max_casper_slashings: 15,
+            max_casper_slashings: 16,
             max_attestations: 128,
             max_deposits: 16,
             max_exits: 16,
+            /*
+             * Validator registry delta flags
+             */
+            activation: 0,
+            exit: 1,
+            /*
+             * Signature domains
+             */
+            domain_deposit: 0,
+            domain_attestation: 1,
+            domain_proposal: 2,
+            domain_exit: 3,
             /*
              * Intialization parameters
              */
@@ -107,6 +129,10 @@ fn initial_validators_for_testing() -> Vec<ValidatorRecord> {
             withdrawal_credentials: Hash256::zero(),
             randao_commitment: Hash256::zero(),
             randao_layers: 0,
+            activation_slot: u64::max_value(),
+            exit_slot: u64::max_value(),
+            withdrawal_slot: u64::max_value(),
+            penalized_slot: u64::max_value(),
             status: From::from(0),
             latest_status_change_slot: 0,
             exit_count: 0,
diff --git a/beacon_chain/spec/src/lib.rs b/beacon_chain/spec/src/lib.rs
index 5b7bdfae37..cc4ce73800 100644
--- a/beacon_chain/spec/src/lib.rs
+++ b/beacon_chain/spec/src/lib.rs
@@ -3,6 +3,7 @@ extern crate types;
 
 mod foundation;
 
+use bls::Signature;
 use types::{Address, Hash256, ValidatorRecord};
 
 #[derive(PartialEq, Debug)]
@@ -16,7 +17,6 @@ pub struct ChainSpec {
     pub max_balance_churn_quotient: u64,
     pub gwei_per_eth: u64,
     pub beacon_chain_shard_number: u64,
-    pub bls_withdrawal_prefix_byte: u8,
     pub max_casper_votes: u64,
     pub latest_block_roots_length: u64,
     pub latest_randao_mixes_length: u64,
@@ -32,20 +32,26 @@ pub struct ChainSpec {
     /*
      * Initial Values
      */
-    pub initial_fork_version: u64,
-    pub initial_slot_number: u64,
+    pub genesis_fork_version: u64,
+    pub genesis_slot_number: u64,
+    pub genesis_start_shard: u64,
+    pub far_future_slot: u64,
     pub zero_hash: Hash256,
+    pub empty_signature: Signature,
+    pub bls_withdrawal_prefix_byte: u8,
     /*
      * Time parameters
      */
     pub slot_duration: u64,
     pub min_attestation_inclusion_delay: u64,
     pub epoch_length: u64,
-    pub min_validator_registry_change_interval: u64,
-    pub pow_receipt_root_voting_period: u64,
-    pub shard_persistent_committee_change_period: u64,
-    pub collective_penalty_calculation_period: u64,
-    pub zero_balance_validator_ttl: u64,
+    pub seed_lookahead: u64,
+    pub min_validator_registry_change_interval: u64, // a.k.a. entry_exit_delay
+    pub pow_receipt_root_voting_period: u64,         // a.k. deposit_root_voting_period
+    pub min_validator_withdrawal_time: u64,
+    pub shard_persistent_committee_change_period: u64, //old
+    pub collective_penalty_calculation_period: u64,    // old
+    pub zero_balance_validator_ttl: u64,               // old
     /*
      * Reward and penalty quotients
      */
@@ -53,6 +59,11 @@ pub struct ChainSpec {
     pub whistleblower_reward_quotient: u64,
     pub includer_reward_quotient: u64,
     pub inactivity_penalty_quotient: u64,
+    /*
+     * Status flags
+     */
+    pub initiated_exit: u64,
+    pub withdrawable: u64,
     /*
      * Max operations per block
      */
@@ -61,6 +72,18 @@ pub struct ChainSpec {
     pub max_attestations: u64,
     pub max_deposits: u64,
     pub max_exits: u64,
+    /*
+     * Validator registry delta flags
+     */
+    pub activation: u64,
+    pub exit: u64,
+    /*
+     * Signature domains
+     */
+    pub domain_deposit: u64,
+    pub domain_attestation: u64,
+    pub domain_proposal: u64,
+    pub domain_exit: u64,
     /*
      * Intialization parameters
      */
diff --git a/beacon_chain/types/src/beacon_state.rs b/beacon_chain/types/src/beacon_state.rs
index b9994bdddb..10d367f197 100644
--- a/beacon_chain/types/src/beacon_state.rs
+++ b/beacon_chain/types/src/beacon_state.rs
@@ -2,7 +2,6 @@ use super::candidate_pow_receipt_root_record::CandidatePoWReceiptRootRecord;
 use super::crosslink_record::CrosslinkRecord;
 use super::fork_data::ForkData;
 use super::pending_attestation_record::PendingAttestationRecord;
-use super::shard_committee::ShardCommittee;
 use super::validator_record::ValidatorRecord;
 use super::Hash256;
 use crate::test_utils::TestRandom;
@@ -30,7 +29,12 @@ pub struct BeaconState {
     // Randomness and committees
     pub latest_randao_mixes: Vec<Hash256>,
     pub latest_vdf_outputs: Vec<Hash256>,
-    pub shard_committees_at_slots: Vec<Vec<ShardCommittee>>,
+    pub previous_epoch_start_shard: u64,
+    pub current_epoch_start_shard: u64,
+    pub previous_epoch_calculation_slot: u64,
+    pub current_epoch_calculation_slot: u64,
+    pub previous_epoch_randao_mix: Hash256,
+    pub current_epoch_randao_mix: Hash256,
 
     // Custody challenges
     pub custody_challenges: Vec<CustodyChallenge>,
@@ -73,7 +77,12 @@ impl Encodable for BeaconState {
         s.append(&self.validator_registry_delta_chain_tip);
         s.append(&self.latest_randao_mixes);
         s.append(&self.latest_vdf_outputs);
-        s.append(&self.shard_committees_at_slots);
+        s.append(&self.previous_epoch_start_shard);
+        s.append(&self.current_epoch_start_shard);
+        s.append(&self.previous_epoch_calculation_slot);
+        s.append(&self.current_epoch_calculation_slot);
+        s.append(&self.previous_epoch_randao_mix);
+        s.append(&self.current_epoch_randao_mix);
         s.append(&self.custody_challenges);
         s.append(&self.previous_justified_slot);
         s.append(&self.justified_slot);
@@ -101,7 +110,12 @@ impl Decodable for BeaconState {
         let (validator_registry_delta_chain_tip, i) = <_>::ssz_decode(bytes, i)?;
         let (latest_randao_mixes, i) = <_>::ssz_decode(bytes, i)?;
         let (latest_vdf_outputs, i) = <_>::ssz_decode(bytes, i)?;
-        let (shard_committees_at_slots, i) = <_>::ssz_decode(bytes, i)?;
+        let (previous_epoch_start_shard, i) = <_>::ssz_decode(bytes, i)?;
+        let (current_epoch_start_shard, i) = <_>::ssz_decode(bytes, i)?;
+        let (previous_epoch_calculation_slot, i) = <_>::ssz_decode(bytes, i)?;
+        let (current_epoch_calculation_slot, i) = <_>::ssz_decode(bytes, i)?;
+        let (previous_epoch_randao_mix, i) = <_>::ssz_decode(bytes, i)?;
+        let (current_epoch_randao_mix, i) = <_>::ssz_decode(bytes, i)?;
         let (custody_challenges, i) = <_>::ssz_decode(bytes, i)?;
         let (previous_justified_slot, i) = <_>::ssz_decode(bytes, i)?;
         let (justified_slot, i) = <_>::ssz_decode(bytes, i)?;
@@ -127,7 +141,12 @@ impl Decodable for BeaconState {
                 validator_registry_delta_chain_tip,
                 latest_randao_mixes,
                 latest_vdf_outputs,
-                shard_committees_at_slots,
+                previous_epoch_start_shard,
+                current_epoch_start_shard,
+                previous_epoch_calculation_slot,
+                current_epoch_calculation_slot,
+                previous_epoch_randao_mix,
+                current_epoch_randao_mix,
                 custody_challenges,
                 previous_justified_slot,
                 justified_slot,
@@ -159,7 +178,12 @@ impl<T: RngCore> TestRandom<T> for BeaconState {
             validator_registry_delta_chain_tip: <_>::random_for_test(rng),
             latest_randao_mixes: <_>::random_for_test(rng),
             latest_vdf_outputs: <_>::random_for_test(rng),
-            shard_committees_at_slots: <_>::random_for_test(rng),
+            previous_epoch_start_shard: <_>::random_for_test(rng),
+            current_epoch_start_shard: <_>::random_for_test(rng),
+            previous_epoch_calculation_slot: <_>::random_for_test(rng),
+            current_epoch_calculation_slot: <_>::random_for_test(rng),
+            previous_epoch_randao_mix: <_>::random_for_test(rng),
+            current_epoch_randao_mix: <_>::random_for_test(rng),
             custody_challenges: <_>::random_for_test(rng),
             previous_justified_slot: <_>::random_for_test(rng),
             justified_slot: <_>::random_for_test(rng),
diff --git a/beacon_chain/types/src/candidate_pow_receipt_root_record.rs b/beacon_chain/types/src/candidate_pow_receipt_root_record.rs
index 5f260c4234..9648763f39 100644
--- a/beacon_chain/types/src/candidate_pow_receipt_root_record.rs
+++ b/beacon_chain/types/src/candidate_pow_receipt_root_record.rs
@@ -3,6 +3,7 @@ use super::Hash256;
 use crate::test_utils::TestRandom;
 use rand::RngCore;
 
+// Note: this is refer to as DepositRootVote in specs
 #[derive(Debug, PartialEq, Clone)]
 pub struct CandidatePoWReceiptRootRecord {
     pub candidate_pow_receipt_root: Hash256,
diff --git a/beacon_chain/types/src/validator_record.rs b/beacon_chain/types/src/validator_record.rs
index 3f4a432616..00e29df649 100644
--- a/beacon_chain/types/src/validator_record.rs
+++ b/beacon_chain/types/src/validator_record.rs
@@ -35,6 +35,10 @@ pub struct ValidatorRecord {
     pub withdrawal_credentials: Hash256,
     pub randao_commitment: Hash256,
     pub randao_layers: u64,
+    pub activation_slot: u64,
+    pub exit_slot: u64,
+    pub withdrawal_slot: u64,
+    pub penalized_slot: u64,
     pub status: ValidatorStatus,
     pub latest_status_change_slot: u64,
     pub exit_count: u64,
@@ -99,6 +103,10 @@ impl Encodable for ValidatorRecord {
         s.append(&self.withdrawal_credentials);
         s.append(&self.randao_commitment);
         s.append(&self.randao_layers);
+        s.append(&self.activation_slot);
+        s.append(&self.exit_slot);
+        s.append(&self.withdrawal_slot);
+        s.append(&self.penalized_slot);
         s.append(&self.status);
         s.append(&self.latest_status_change_slot);
         s.append(&self.exit_count);
@@ -114,6 +122,10 @@ impl Decodable for ValidatorRecord {
         let (withdrawal_credentials, i) = <_>::ssz_decode(bytes, i)?;
         let (randao_commitment, i) = <_>::ssz_decode(bytes, i)?;
         let (randao_layers, i) = <_>::ssz_decode(bytes, i)?;
+        let (activation_slot, i) = <_>::ssz_decode(bytes, i)?;
+        let (exit_slot, i) = <_>::ssz_decode(bytes, i)?;
+        let (withdrawal_slot, i) = <_>::ssz_decode(bytes, i)?;
+        let (penalized_slot, i) = <_>::ssz_decode(bytes, i)?;
         let (status, i) = <_>::ssz_decode(bytes, i)?;
         let (latest_status_change_slot, i) = <_>::ssz_decode(bytes, i)?;
         let (exit_count, i) = <_>::ssz_decode(bytes, i)?;
@@ -127,6 +139,10 @@ impl Decodable for ValidatorRecord {
                 withdrawal_credentials,
                 randao_commitment,
                 randao_layers,
+                activation_slot,
+                exit_slot,
+                withdrawal_slot,
+                penalized_slot,
                 status,
                 latest_status_change_slot,
                 exit_count,
@@ -146,6 +162,10 @@ impl<T: RngCore> TestRandom<T> for ValidatorRecord {
             withdrawal_credentials: <_>::random_for_test(rng),
             randao_commitment: <_>::random_for_test(rng),
             randao_layers: <_>::random_for_test(rng),
+            activation_slot: <_>::random_for_test(rng),
+            exit_slot: <_>::random_for_test(rng),
+            withdrawal_slot: <_>::random_for_test(rng),
+            penalized_slot: <_>::random_for_test(rng),
             status: <_>::random_for_test(rng),
             latest_status_change_slot: <_>::random_for_test(rng),
             exit_count: <_>::random_for_test(rng),
diff --git a/beacon_chain/utils/bls/src/signature.rs b/beacon_chain/utils/bls/src/signature.rs
index 242908e21e..bd363e34a6 100644
--- a/beacon_chain/utils/bls/src/signature.rs
+++ b/beacon_chain/utils/bls/src/signature.rs
@@ -35,6 +35,12 @@ impl Signature {
     pub fn as_raw(&self) -> &RawSignature {
         &self.0
     }
+
+    /// Returns a new empty signature.
+    pub fn empty_sig() -> Self {
+        let empty: Vec<u8> = vec![0; 97];
+        Signature(RawSignature::from_bytes(&empty).unwrap())
+    }
 }
 
 impl Encodable for Signature {
@@ -68,4 +74,16 @@ mod tests {
 
         assert_eq!(original, decoded);
     }
+
+    #[test]
+    pub fn test_empty_sig() {
+        let sig = Signature::empty_sig();
+
+        let sig_as_bytes: Vec<u8> = sig.as_raw().as_bytes();
+
+        assert_eq!(sig_as_bytes.len(), 97);
+        for one_byte in sig_as_bytes.iter() {
+            assert_eq!(*one_byte, 0);
+        }
+    }
 }
diff --git a/beacon_chain/validator_induction/src/inductor.rs b/beacon_chain/validator_induction/src/inductor.rs
index f00c9ec55f..fd8768cd2e 100644
--- a/beacon_chain/validator_induction/src/inductor.rs
+++ b/beacon_chain/validator_induction/src/inductor.rs
@@ -44,6 +44,10 @@ pub fn process_deposit(
                 withdrawal_credentials: deposit_input.withdrawal_credentials,
                 randao_commitment: deposit_input.randao_commitment,
                 randao_layers: 0,
+                activation_slot: spec.far_future_slot,
+                exit_slot: spec.far_future_slot,
+                withdrawal_slot: spec.far_future_slot,
+                penalized_slot: spec.far_future_slot,
                 status: ValidatorStatus::PendingActivation,
                 latest_status_change_slot: state.validator_registry_latest_change_slot,
                 exit_count: 0,