Here is the full list of all 11 Party Pumper achievements.
Gain 100% vibe on Electro Club party!
Gain 100% vibe on Pool party!
Gain 100% vibe on hard difficulty!
Perform 3 types of dances
Play all samples to the beat during one party
Throw the party pooper into the crowd
Don't let the party pooper jump into the pool
Use both slider FX at the same moment
Have some proper drink
Hit some flying baloons with fireworks
Complete the tutorial