diff --git a/README.md b/README.md
index ec0f932..acca5d7 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# dropblocks
+# DROPBLOCK
 Simple block-dropping game for Apple II
 
 BRUN DROPBLOCK
@@ -14,3 +14,16 @@ Match colors to make blocks disappear. Bonus points for matching 4 blocks at onc
 
 Progress indicator at bottom of screen shows how many more points you need until the next "level" where things get a little more difficult.
 
+# BLOCKCHAIN
+Updated variant, based on DROPBLOCK.
+
+BRUN BLOCKCHAIN
+
+Game starts in self playing "attract mode". 
+Press SPACE to start your game. 
+R to reset/restart. 
+ESC to quit.
+
+Press J and L to move the dropping blocks left and right. 
+
+Match colored blocks to form "block chains" of progressive colors. Red blocks combine to make Orange, Orange blocks combine to yellow, and so on. Each level adds another type of chain to form, and gets a little faster.