Item description:

Footy Foul (Kill 2 enemies with 1 Slide Kick during Slow Mo)
Doll Collector (Find the Alma Doll on every Mission)
Spiritually Attuned (Make 100 Psychic Links (Share or Steal))
Supreme Challenger (Complete 500 total challenges between all categories)
Completionist (Complete every challenge at least once)
No can defense! (Kill 100 enemies with Jump Kick or Slide Kick)
God Among Men (Kill 250 total enemies during Slow Mo)

The following will unlock after doing 1 of each thing

Insider Trading (Possess every type of possessable enemy)
Art Collector (Pin 100 total enemies with The Penetrator or Leaper knives)
Head Crab Removal (20 kills with a crowbar)
Little Brother's Helper (As Point Man, kill 100 enemies suspended by Fettel)
Big Brother's Helper (As Fettel, suspend 100 enemies that Point Man kills)
I'm not a Doctor, I'm a Medic! (Perform 50 revives in any game mode)
Monarch (Win 20 rounds of Soul King)

I beat a level on insane and got the achievement for beating them all on insane so it might unlock if you beat it on a different difficulty also unlocked the kill 100 enemies suspended by Fettel and revive 50 times when I did each once.

Playing as Fettel I got the brothers helper, crowbar, art collector and possession achievements

Playing online got me the 20 wins in Soul King after 1 win