|This article is about a/an half form in Kamen Rider Build.|
- Kamen Rider Build Hazard Forms
- RabbitTank (Build Episodes 20-21, Raising the Hazard Level ~7 Best Matches~: Final Chapter, Build 22-26)
- SmaphoWolf (Raising the Hazard Level ~7 Best Matches~: First Chapter)
- HawkGatling (Build Episode 22)
- KaizokuRessya (Build Episode 24, 35)
- KeyDragon (Build Episode 35)
- RabbitRabbit Form (Build Episodes 27-36, 38-40, 45, Be The One, 49)
- TankTank Form (Build Episodes 28-33, 35-36, 40, 43-44, Be The One, 48-49)
- Kamen Rider Metal/Phantom Build (Kamen Rider Build NEW WORLD: Kamen Rider Grease)
Build's Hazard Forms have two finishers:
- Rider Punch + Rider Kick: This finisher has two variations:
- Rider Punch: Build transfers surplus Nebula Gas into his HZ Deadly Gloves and delivers a powerful punch, summoning a wolf-like energy projection which "bites" down on the enemy.
- KaizokuRessya: Build repeatedly punches the enemy with his HZ Deadly Gloves delivering purple shockwaves on impact.
- Rider Kick: This finisher has two variations:
- Build release an electricity from his HZ Deadly Glove to paralyze the enemy, then coats his right HZ Vanish End Shoe in purple, dark energy before delivering a powerful side kick.
- Build rushes towards the enemy and performs a flying kick.
- Rider Shooting: Build traps the enemy in a black cloud and performs a series of purple blasts with the Hawk Gatlinger.
Build's finisher for RabbitRabbit Form is the RabbitRabbit Finish (ラビットラビットフィニッシュ Rabitto Rabitto Finisshu): Jumping into the air, Build stretches his leg towards the opponent, and pulling his body towards his foot, connects with an elastic kick at the target, with the resulting impact sending his opponent flying.
- Hazard Attack (ハザードアタック Hazādo Atakku): Metal Build jumps into the air before crashing into the target with a double knee drop. He then creates an energy tank tread that grinds the enemy into the ground.
- Hazard Finish (ハザードフィニッシュ Hazādo Finisshu): Metal Build performs a roundhouse kick motion towards the opponent, creating a tank track that flies into the target and grinds against them, acting like a chainsaw. This attack can strike multiple opponents.
- Hazard Finish (ハザードフィニッシュ Hazādo Finisshu): Phantom Build launches a volley of missiles from his back before performing two consecutive roundhouse kicks towards the opponent, creating a tank track that flies into the target.
- Another set of Hazard Halfbodies appeared as Build first transformed into KeyDragon Hazard.