Supporters are Rabbid enemies in Mario + Rabbids: Kingdom Battle, identifiable by their backpacks topped with a red siren. As their name implies, they specialize in supporting their teammates; their main claim to fame is their ability to heal themselves and all allies within a certain range. They can also throw bombs that ignore cover bonuses, destroy Giant Brick Blocks, and have a high chance to inflict status effects on any character caught in the blast.
There are three Supporter variants, one for each area apart from Ancient Gardens.
Sherbet Supporter: Encountered in Sherbet Desert, this Supporter has 165 HP. It wears a shell-like backpack, a furry collar, and a bodysuit resembling a cactus.
Spooky Supporter: Encountered in Spooky Trails, this 250 HP Supporter appears to be undead, with a pale body, glowing blue eyes, and a melting candle on its head.
Lava Supporter: The final Supporter variant is encountered in the Lava Pits, with a charred appearance, glowing orange eyes, a Bowser Jr. bandanna on its chest, and 375 HP.
While there aren't any Supporters in the Donkey Kong Adventure DLC, there is an enemy type called the Summoner that acts similarly to a Supporter, with the addition of being able to summon additional enemies, though it takes them a one-turn wait to summon enemies