It seems to me that Devastator is the granddaddy of TF combiners. The original. The one that started it all. (And no, Reflector doesn't count. That's a totally different concept despite its quasi-combined mode into not a robot.) It also seems to me that Constructor is the best option for MP-esque Devastator, without a close second. And it will remain so for at least a couple of years. No other MP Devastators are even planned, let alone will release before the next 2 years, at the very earliest.