Here is the full list of all 31 Pummel Party achievements.
Survive for at least 50 seconds in 'Sorcerers Sprint'
As the lightning holder kill every other player in 'Thunderous Trench'
Died in 'Acidic Atoll' throwing a barrel
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
Survive in 'Breaking Blocks' for 60 seconds
Control over 50% of the area in 'Elemental Escalation'
Start your first game
Score over 5 in 'Bouncing Balls'
Collect 40 keys in 'Winter Maze'
Complete 'Slippery Sprint' without falling in the water
Win your first game
Find the treasure in 'Sandy Search'
Complete 'Rusty Racers' without falling off the track
Steal the last gift in a players pile in 'Grifting Gifts'
Get launched off screen in 'Tunneling Tanks'
Get a double kill in 'Barn Brawl'
Get your first goal
Win your first minigame
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'
Knockout 10 players in one game of 'Explosive Exchange'
Got hit by the train in 'Temporal Trails'
Win 'Magma & Mages' without taking damage
Complete 'Gift Grab' without collecting coal