Medals:
Pardon Me: Kill 3 enemies using a single rocket jump.
Quickdraw: Kill 6 enemies instantaneously using a pistol and the "Gun Kata" master trait.
Woodchipper: Kill 5 or more enemies instantaneously using a melee weapon and the "Blademaster" master trait.
This is My Boomstick: Put 9 mods on a shotgun.
Run and Gun: Kill 10 enemies in a single running session.
Toreador: Sidestep projectiles from 5 different enemies at once.
It's More Doomish This Way: Win AoB without ever picking up the LS.
Make the Most of It: Kill 10 enemies in a single invincibility session.
Ranks (You must play on Medium or harder)
Ass-Kicker[1-4]: Win the game with 100% kills.*
Crazy Bastard[1-4]: Clear the Mortuary.*
Crazy Awesome[1-4]: Clear the mortuary. No plasma cells allowed!*
Dextrous Digits[1-5]: Win the game in [35, 30, 27, 24, 20] or fewer realtime minutes.
Shotgunner[1-4]: Win the game without ever firing a non-shotgun weapon.*
Speed Demon[1-5]: Win the game in [60, 55, 50, 45, 40] or fewer ingame minutes.
*The rank you get is based on what difficulty you did it on, not including Easy of course.