Red-Brief J

Red-Brief J is the boss of Thrillsville in Wario World. He's a large, bipedal, anthropomorphic bull, who, as his name suggests, is clad in red undergarments, as well as a metallic helmet. His body is covered in a few scorch marks.

The battle takes place on a metal platform suspended over a pool of lava, located in a snowy canyon. Red-Brief J has the largest variety of attacks of any of the bosses in the game. Before he starts any attack, he will strut around after Wario with his hooves on his hips. Wario must not go near his feet when he does this, because fire erupts from them while he's walking. In his first and most common attack, he absorbs orange energy and charges toward Wario at full speed. The number of charges equals six minus the current HP.

Red-Brief J's second attack is to point and shoot homing fireballs from the hooves on his arms. His third attack only happens when he has taken damage. It involves drawing in purple energy and jumping extremely high, then landing at the middle, briefly dunking half the arena in lava. Wario must stand on the middle area to avoid this attack. His fourth attack happens when he's on 2-3 HP. He jumps in the air and starts spinning while drawing in blue energy. He starts front-flipping and then dives head-first into Wario.

In Red-Brief J's final attack, he draws in pink energy and spins around, while homing towards Wario.

Red-Brief J is immune to all of Wario's direct attacks, and he will counter-attack with one of his own moves (possibly including the twirling move, even if he has high health) if Wario punches him. After he uses his charging attack, Red-Brief J will teeter off the edge of the platform. If Wario Ground Pounds the center of the arena during this time, Red-Brief J will get knocked into the lava, release a huge amount of coins and lose one hit point out of five. After this, he'll return to the center of the arena and resume attacking. After losing all five hit points, Red-Brief J explodes and Wario receives the third piece of the Huge Treasure Chest Key and gains access to Sparkle Land.

Trivia

 * Red-Brief J, along with DinoMighty, are the only bosses to appear in the video game's official artwork.
 * This character seems to draw inspiration from Bīfun, one of the bosses from the first Wario Land game.
 * Red-Brief J is one of two bosses who can't become stunned; the other being Ironsider.