Fernus the burning is what a competent J'onn looks like. There's not much he did that MM couldn't do with his natural power set.
Only other thing that comes close is All Access MM disguising himself as Cap to sucker punch Thor, using his tp to mind screw in JLA Avengers, and most of Ostranders MM series.
So basically, you need a top herald like Surfer or Strange, or some other more powerful "jack of all trades" to really fight him.
Originally posted by Board Walker
MM would beat any high herals such as silver surfer, thor, etc., it would require a trans with a powerset that is similar to his but outrightly more powerful.
Nope on beating Silver Surfer. Of course a competent J'onn beats Thor, since competent people remember they have high levels of super speed, it's a weird thing they do..remembering to use the powers they actually possess.