Garugaru are the monsters that show up throughout Wonderful Pretty Cure!. They start out as black and yellow eggs before hatching into big, dark creatures with grey and red masks.
The thing about Garugaru is that they're actually corrupted versions of animals from the Niko Garden. Since there's still an animal underneath all that corruption, the Cures don't just beat them up—instead, they try to reach the creature's original nature by playing with them and reconnecting them to who they really are.
By episode 29, things escalate when Torame and Zakuro join the cast. The monsters get upgraded into a stronger form called Gaogaon. Torame still hatches them from eggs like before, but Zakuro brings a different approach, corrupting animals straight from Animal Town instead.
Content compiled by AnimeList.moe from publicly available sources.
