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