Similar to the Stunner but instead of dropping the opponent neck first onto the attacker's shoulder, the attacker drives their opponent face-first down. Named after it's creator Johnny Ace. An Ace Crusher is typically one handed. Various variations of the move exist.
See Apache Cutter for more details.
The Diamond Cutter or Cutter for short was a variation innovated by Diamond Dallas Page. Unlike the Ace Crusher, the Diamond Cutter is two handed as the attacker wraps their opponent in a Cravate headlock before dropping the victim face-first onto the mat.
Fireman's Carry Ace Crusher
The Fireman's Carry Ace Crusher or TKO is an Ace Crusher variation out of fireman's carry. The TKO name comes from its innovator, Marc Mero.
Jumping Ace Crusher
The Jumping Ace Crusher or RKO is an Ace Crusher where the attacker leaps into the move. The RKO name comes from its innovator, Randy Orton.
Rolling Ace Crusher
The Rolling Ace Crusher or also known as the Last Rites, Roll of the Dice, Hero's Welcome, Spin Doctor and Test Drive is an Ace Crusher variation but spun out of an inverted facelock. Popularized by Christopher Daniels who gave it the name Last Rites.