Here is the full list of all 14 Weird Hat Fight achievements.
Played Orbit map
Collected 10 hats
Collected 1 hat
Completed 1 match
Played Crafts map
Completed 10 matches
Completed 50 matches
Completed 100 matches
Collected 50 hats
Collected 100 hats
Played on all maps
Play the game with 4 players
Played Arena map
Played Propeller map