Here is the full list of all 13 Unnamed Fiasco achievements.
Keep the flag for two straight minutes in Capture the Flag mode.
Perform 3 Triple Kills in a single match.
Retrieve 5 Treasures in a row in Treasure Hunt mode.
Do not get killed in a Police Chase game.
Get five kills without using your gun.
Get most of your kills when the Minute Madness is enabled.
Win by scoring more points than all other players combined (in 3 or 4-player mode).
Be the first one to capture the flag and never let go of it.
All players have died in a short period of time (in 4-player mode).
Win a Dog Tag game with least kills.
Be the player with fewer points at sometime and still win the game (in 3 or 4-player mode).
Kill at least one player every time you are the police in a Police Chase game.
Achieve 100% in the single player challenges.