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