Deadpool

To be clear, you can push and teleport, but if ever you push and Deadpool counters an enemy attack (you will know because there will be a 60's Batman sounding POW! cue) good job, you screwed up.

Should be no problem if you quickly pause and reload checkpoint.

The trickiest part of this level is the Blockbuster fight. He can't be hurt unless he's stunned and the fight is intentionally set up in a way meant to make you counter him. The game will tease you with a prompt when Blockbuster charges you. Don't push it, obviously. Use a stun grenade on him instead.

On easiest difficulty, this achievement isn't too bad. The worst part is the length of the level

Its a bit of a pain on hard only because of the Blockbuster boss fight (and playing as Rogue. she can't parry, but she sucks and will die a lot)

Best point of advice dealing with Blockbuster on hardest difficulty is to make sure you have purchased plasma rifles and the "I know gun-fu" perk for them. Equip the Plasmas and use gunkata on Blockbuster. If you don't know what that is, its pushing during a melee combo. Deadpool will shoot nearby enemies without having to aim.

Once stunned, swing your melee weapon into Blockbuster once, then start hammering and unload on him. For some reason, even if you don't have the guns fully powered up, gunkata will mess him up badly and should defeat him within 2-4 combos.

The most annoying thing that will happen during this fight is Blockbuster picking up and throwing a piece of floor at you. Even if stunned, he will continue the throw animation and will not take damage until finished. You lose a second or two of stun time waiting for him to do that.

As far as the finale with Rogue goes, there's a combo she has that makes the fight much easier. I don't remember what it is exactly, but I think its x,y,y,y,x. The combo you want to rely on is a series of cartwheel kicks. They deal high damage, tend to be blocked less, and most importantly help her slow ass cover more ground.

Good luck!

Not a guide but my method is assign the "B button" to another button

This achievement is really annoying to me, I re-played the whole chapter "Land in Prison" twice but still didn't get it, I thought I need to find a method to disable the B button.

Go to Setting > Kinect & devices > Devices & accessories > Configure > Button mapping

I changed my "B button" to "Right Stick Click", I played this chapter again, with no worry on accidentally counter and got this achievement.