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