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