diff --git a/beacon_node/beacon_chain/tests/block_verification.rs b/beacon_node/beacon_chain/tests/block_verification.rs
index 078a5d848c..415aed5831 100644
--- a/beacon_node/beacon_chain/tests/block_verification.rs
+++ b/beacon_node/beacon_chain/tests/block_verification.rs
@@ -206,6 +206,10 @@ fn update_blob_signed_header<E: EthSpec>(
     signed_block: &SignedBeaconBlock<E>,
     blobs: &mut BlobSidecarList<E>,
 ) {
+    // Required to prevent as_mut_slice being called on an uninitialized list. Yuck.
+    if blobs.is_empty() {
+        return;
+    }
     for old_blob_sidecar in blobs.as_mut_slice().unwrap() {
         let new_blob = Arc::new(BlobSidecar::<E> {
             index: old_blob_sidecar.index,
diff --git a/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs b/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs
index f5e3e560ec..a190b3fb75 100644
--- a/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs
+++ b/beacon_node/execution_layer/src/test_utils/execution_block_generator.rs
@@ -672,7 +672,7 @@ impl<E: EthSpec> ExecutionBlockGenerator<E> {
             // get random number between 0 and Max Blobs
             let mut rng = self.rng.lock();
             // TODO(pawan): thread the chainspec value here somehow
-            let num_blobs = rng.gen::<usize>() % 6;
+            let num_blobs = rng.gen::<usize>() % (6 + 1);
             let (bundle, transactions) = generate_blobs(num_blobs)?;
             for tx in Vec::from(transactions) {
                 execution_payload