diff --git a/basilisk/basilisk.c b/basilisk/basilisk.c
index b774463d3..c438a7398 100755
--- a/basilisk/basilisk.c
+++ b/basilisk/basilisk.c
@@ -595,8 +595,8 @@ int32_t basilisk_blocksend(struct supernet_info *myinfo,struct iguana_info *btcd
     hash2 = iguana_blockhash(virt,height);
     if ( (blocklen= iguana_peerblockrequest(virt,virt->blockspace,IGUANA_MAXPACKETSIZE,0,hash2,0)) > 0 )
     {
-        printf("RELAYID.%d send block.%d -> (%s) %s\n",myinfo->RELAYID,height,addr->ipaddr,bits256_str(str,hash2));
         blockstr = basilisk_addhexstr(&allocptr,0,strbuf,sizeof(strbuf),&virt->blockspace[sizeof(struct iguana_msghdr)],blocklen);
+        printf("RELAYID.%d send block.%d %s -> (%s) %s\n",myinfo->RELAYID,height,blockstr,addr->ipaddr,bits256_str(str,hash2));
         basilisk_blocksubmit(myinfo,btcd,virt,addr,blockstr,virt->blocks.hwmchain.RO.hash2,height);
         if ( allocptr != 0 )
             free(allocptr);
diff --git a/gecko/gecko_blocks.c b/gecko/gecko_blocks.c
index 762188f81..467896c46 100755
--- a/gecko/gecko_blocks.c
+++ b/gecko/gecko_blocks.c
@@ -172,7 +172,7 @@ int32_t gecko_hwmset(struct supernet_info *myinfo,struct iguana_info *virt,struc
 
 char *gecko_blockarrived(struct supernet_info *myinfo,struct iguana_info *virt,char *remoteaddr,uint8_t *data,int32_t datalen,bits256 hash2,int32_t verifyonly)
 {
-    struct iguana_txblock txdata; int32_t height,valid,adjacent,gap,n,i,j,len = -1; struct iguana_block *block,*prev; struct iguana_txid tx; char str[65]; bits256 txid; struct iguana_msgtx *txs;
+    struct iguana_txblock txdata; int32_t height,valid,adjacent,gap,n,i,j,len = -1; struct iguana_block *block,*prev; struct iguana_txid tx; char str[65]; bits256 txid,threshold; struct iguana_msgtx *txs;
     memset(&txdata,0,sizeof(txdata));
     iguana_memreset(&virt->TXMEM);
     if ( (n= iguana_gentxarray(virt,&virt->TXMEM,&txdata,&len,data,datalen)) == datalen )
@@ -182,6 +182,14 @@ char *gecko_blockarrived(struct supernet_info *myinfo,struct iguana_info *virt,c
             printf("gecko_blockarrived: mismatched hash2\n");
             return(clonestr("{\"error\":\"gecko block hash2 mismatch\"}"));
         }
+        if ( txdata.zblock.RO.bits >= GECKO_EASIESTDIFF )
+            bits256_from_compact(GECKO_EASIESTDIFF);
+        else threshold = bits256_from_compact(txdata.zblock.RO.bits);
+        if ( bits256_cmp(threshold,hash2) <= 0 )
+        {
+            printf("gecko_blockarrived: failed nBits diff\n");
+            return(clonestr("{\"error\":\"gecko block failed nBits diff\"}"));
+        }
         txs = virt->TXMEM.ptr;
         for (i=0; i<txdata.zblock.RO.txn_count; i++)
         {