diff --git a/eth2/state_processing/src/per_block_processing.rs b/eth2/state_processing/src/per_block_processing.rs
index ac874d95e..331069d44 100644
--- a/eth2/state_processing/src/per_block_processing.rs
+++ b/eth2/state_processing/src/per_block_processing.rs
@@ -139,6 +139,8 @@ pub fn verify_block_signature(
         &state.fork,
     );
 
+    println!("verify {:?}", &block);
+
     verify!(
         block
             .signature
diff --git a/eth2/state_processing/src/per_block_processing/block_processing_builder.rs b/eth2/state_processing/src/per_block_processing/block_processing_builder.rs
index 489684523..fb9dbd153 100644
--- a/eth2/state_processing/src/per_block_processing/block_processing_builder.rs
+++ b/eth2/state_processing/src/per_block_processing/block_processing_builder.rs
@@ -30,7 +30,7 @@ impl BlockProcessingBuilder {
         self.state_builder.build_caches(&spec).unwrap();
     }
 
-    pub fn build(mut self, spec: &ChainSpec) -> (BeaconBlock, BeaconState) {
+    pub fn build(mut self, randao_sk: Option<SecretKey>, spec: &ChainSpec) -> (BeaconBlock, BeaconState) {
         let (state, keypairs) = self.state_builder.build();
         let builder = &mut self.block_builder;
 
@@ -41,10 +41,14 @@ impl BlockProcessingBuilder {
             .unwrap();
         let keypair = &keypairs[proposer_index];
 
-        builder.set_randao_reveal(&keypair.sk, &state.fork, spec);
+        match randao_sk {
+            Some(sk) => builder.set_randao_reveal(&sk, &state.fork, spec),
+            None => builder.set_randao_reveal(&keypair.sk, &state.fork, spec),
+        }
 
         let block = self.block_builder.build(&keypair.sk, &state.fork, spec);
 
         (block, state)
     }
+
 }
diff --git a/eth2/state_processing/src/per_block_processing/tests.rs b/eth2/state_processing/src/per_block_processing/tests.rs
index 6fe7e40d2..6ae7fd872 100644
--- a/eth2/state_processing/src/per_block_processing/tests.rs
+++ b/eth2/state_processing/src/per_block_processing/tests.rs
@@ -11,7 +11,7 @@ pub const VALIDATOR_COUNT: usize = 10;
 fn valid_block_ok() {
     let spec = ChainSpec::foundation();
     let builder = get_builder(&spec);
-    let (block, mut state) = builder.build(&spec);
+    let (block, mut state) = builder.build(None, &spec);
 
     let result = per_block_processing(&mut state, &block, &spec);
 
@@ -22,7 +22,7 @@ fn valid_block_ok() {
 fn invalid_block_header_state_slot() {
     let spec = ChainSpec::foundation();
     let builder = get_builder(&spec);
-    let (mut block, mut state) = builder.build(&spec);
+    let (mut block, mut state) = builder.build(None, &spec);
 
     state.slot = Slot::new(133713);
     block.slot = Slot::new(424242);
@@ -47,7 +47,7 @@ fn invalid_parent_block_root() {
 fn invalid_block_signature() {
     let spec = ChainSpec::foundation();
     let builder = get_builder(&spec);
-    let (mut block, mut state) = builder.build(&spec);
+    let (mut block, mut state) = builder.build(None, &spec);
 
     // sign the block with a keypair that is not the expected proposer
     let keypair = Keypair::random();
@@ -66,6 +66,24 @@ fn invalid_block_signature() {
     );
 }
 
+#[test]
+fn invalid_randao_reveal_signature() {
+    let spec = ChainSpec::foundation();
+    let builder = get_builder(&spec);
+
+    // sign randao reveal with random keypair
+    let keypair = Keypair::random();
+    let (block, mut state) = builder.build(Some(keypair.sk), &spec);
+    
+    let result = per_block_processing(&mut state, &block, &spec);
+
+    // should get a BadRandaoSignature error
+    assert_eq!(
+        result,
+        Err(BlockProcessingError::Invalid(BlockInvalid::BadRandaoSignature))
+    );
+}
+
 fn get_builder(spec: &ChainSpec) -> (BlockProcessingBuilder) {
     let mut builder = BlockProcessingBuilder::new(VALIDATOR_COUNT, &spec);
 
diff --git a/eth2/types/src/test_utils/testing_beacon_block_builder.rs b/eth2/types/src/test_utils/testing_beacon_block_builder.rs
index c5cd22ed4..c8c32d931 100644
--- a/eth2/types/src/test_utils/testing_beacon_block_builder.rs
+++ b/eth2/types/src/test_utils/testing_beacon_block_builder.rs
@@ -33,6 +33,7 @@ impl TestingBeaconBlockBuilder {
     /// Modifying the block after signing may invalidate the signature.
     pub fn sign(&mut self, sk: &SecretKey, fork: &Fork, spec: &ChainSpec) {
         let message = self.block.signed_root();
+        println!("block set {:?}", self.block);
         let epoch = self.block.slot.epoch(spec.slots_per_epoch);
         let domain = spec.get_domain(epoch, Domain::BeaconBlock, fork);
         self.block.signature = Signature::new(&message, domain, sk);
@@ -48,6 +49,11 @@ impl TestingBeaconBlockBuilder {
         self.block.body.randao_reveal = Signature::new(&message, domain, sk);
     }
 
+    /// Has the randao reveal been set?
+    pub fn randao_reveal_not_set(&mut self) -> bool {
+        self.block.body.randao_reveal.is_empty()
+    }
+
     /// Inserts a signed, valid `ProposerSlashing` for the validator.
     pub fn insert_proposer_slashing(
         &mut self,