Party Balloon

Party Balloon (Korean: 파티 풍선, pati pungson) is an Epic Pet released that was alongside its owner,, in the first half of the Happy Cookie Festival update. This Pet slowly grows in size as Jellies are collected, eventually popping and creating even more Jellies.

Story
''A balloon that's super excited to eat Jellies at a party. It's already decorated itself with a party hat and ribbons! But maybe it was a bit too excited? After eating too much, it's become stuffed with Jellies to the brim. It's not going to pop, is it? Oh no! Cover your ears!''

Trivia

 * Party Balloon may partially be a reference to whoopee cushions due to its ridiculous, comedic deflation.