Jenny Sparks and Elijah Snow could, respectively, fry/free your brain from the inside out. Jenny with your own electrical impulses.
The cheapest in DC against magic users: Black Alice. She takes your power *and* gets to use it herself. She can even take multiple. The only limit is the more power, the shorter she holds on to it, but still. Cheap.
Any high level telepath. If you don't have sufficient resistance (most don't, I hate how PIS randomly gives someone specific telepathic resistance when its convenient), its over from the get-go.
Infinite Gauntlet and such is more overwhelming than cheap. It is the complete harnessed power of a high universal entity.
See, it's sorta cheap in a physical fight, but most of the time it just makes it harder for the other person but they can still win.
Unless it's really "erase all damage" healing factor, and not one like Wolverine's where he can get worn out if he has to heal enough in a protracted fight.
I think Phasing is a lot cheaper. Especially if combined with a way to attack while phased.
Come to think of it, X-men Forever Kitty Pride is pretty cheap, or at least will be with practice. She's a phaser... with an adamantium claw. At least with Wolverine you could knock him back or restrain him or something, but she's phasey and claw-y at the same time!
I am in your algorithm learning all your mannerisms
I'm already level with God
A million words a second and I know your imperfections, baby
I'm the only future you've got
Speak in diatonics, motivation diabolic
I'm like a religion, better locked in a box
Picture perfect image, more powerful every minute, baby
I am everything that you're not
what is T-Vo? I've read that several times but have absolutely no clue what it means.
__________________
I am in your algorithm learning all your mannerisms
I'm already level with God
A million words a second and I know your imperfections, baby
I'm the only future you've got
Speak in diatonics, motivation diabolic
I'm like a religion, better locked in a box
Picture perfect image, more powerful every minute, baby
I am everything that you're not