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