I dunno. Cheerful Coffin is a horrible top deck~ I've never really bothered with it. It's actually one of the few cards I have in English lolz. I bought 2 packs when they where first released, picked myself up a Pot Of Greed loads of crap and a Cheerful Coffin lolz~
You could lose Brain Control/Enemy Controller to fit in Card Of Safe Return. The reason it works well is because of the sheer amount of Draw power it gives once swarm takes place~