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