Here is the full list of all 31 Pummel Party achievements.
Place last in every minigame
Survive in 'Breaking Blocks' for 60 seconds
Died in 'Acidic Atoll' throwing a barrel
Complete 'Gift Grab' without collecting coal
Knock off 5 players in one game of 'Snowy Spin'
Got hit by the train in 'Temporal Trails'
Survive for 50 seconds in 'Bullet Barrage'
Place first in every minigame
Complete 'Rusty Racers' without falling off the track
Control over 50% of the area in 'Elemental Escalation'
Win 'Magma & Mages' without taking damage
Take no damage in 'Searing Spotlights' minigame
Score over 5 in 'Bouncing Balls'
As the lightning holder kill every other player in 'Thunderous Trench'
Win your first game
Knockout 10 players in one game of 'Explosive Exchange'
Get a double kill in 'Barn Brawl'
Hit three players with the remote control eggplant
Skewer three players with the rocket skewer item
Get a 5 player kill sreak in 'Speedy Sabers'
Complete 'Slippery Sprint' without falling in the water
Collect 40 keys in 'Winter Maze'
Survive for at least 50 seconds in 'Sorcerers Sprint'
Get launched off screen in 'Tunneling Tanks'
Steal the last gift in a players pile in 'Grifting Gifts'
Get your first goal
Accidentally blew yourself up in the 'Strategic Shockwave' minigame
Find the treasure in 'Sandy Search'
Win your first minigame
Start your first game