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