Aerodent is the boss of the Topaz Passage in Wario Land 4. It is a that a small mouse (or rat) that utilizes an giant inflatable bear in order to fly high enough to dive-bomb Wario using its abnormally sharp tail.
Wario reacts by throwing the rodent back into the inflatable bear to deflate the balloon, then attacking the bear's feet to turn it upside down and attack the mouse while it blows more air into the bear. When it's health starts getting low it begins sending down fireballs at Wario to try and set him on fire. When defeated the mouse seemingly escapes but the inflatable bear explodes.