diff --git a/js/format-c2g.js b/js/format-c2g.js
index 352da4f..23cf749 100644
--- a/js/format-c2g.js
+++ b/js/format-c2g.js
@@ -355,7 +355,10 @@ const TILE_ENCODING = {
         name: 'bomb',
         has_next: true,
     },
-    //0x41: Open trap (unused in main levels) : 
+    0x41: {
+        // FIXME cc2lp1 uses this, i don't know what it actually does
+        error: "Open trap is not yet implemented!",
+    },
     0x42: {
         name: 'trap',
     },
diff --git a/js/tiletypes.js b/js/tiletypes.js
index b4dd3f0..f3cc90f 100644
--- a/js/tiletypes.js
+++ b/js/tiletypes.js
@@ -1843,7 +1843,7 @@ const TILE_TYPES = {
         movement_parity: 2,
         decide_movement(me, level) {
             let preference = pursue_player(me, level);
-            if (level.player.type.name === 'player2') {
+            if (preference && level.player.type.name === 'player2') {
                 // Run away from Cerise
                 for (let [i, direction] of preference.entries()) {
                     preference[i] = DIRECTIONS[direction].opposite;