Introduction
Released in 1989, X Multiply is a horizontal scrolling shoot 'em up by Irem that combined biological horror with intense arcade action. Often compared to R-Type, this lesser-known gem featured unique gameplay mechanics and grotesque visuals that made it stand out in the genre.

Development and History
- Developer: Irem
- Publisher: Irem
- Release Date: 1989 (Arcade)
- Hardware: Irem M72 system board
X Multiply was developed shortly after R-Type II and shares much of its aesthetic and gameplay DNA. However, instead of a space setting, the game takes place inside a human body infected by alien parasites. This concept allowed Irem’s artists and programmers to flex their creativity with pulsating environments and organic level design.
The game’s central mechanic — a pair of tentacle-like appendages — provided both offense and defense, making the gameplay feel distinct from traditional shooters.

Gameplay Video
Gameplay and Mechanics
Players control a microscopic ship that’s been injected into an infected human to eliminate alien threats from within. Unlike R-Type's detachable Force Pod, X Multiply’s key innovation lies in its dual bio-mechanical tentacles that extend and whip around in response to player movement.
Key mechanics:
- Tentacle arms: Can block projectiles and deal damage by whipping around enemies
- Power-ups: Enhance firepower, speed, and tentacle control
- Scrolling levels: Horizontally oriented with biological hazards and tight corridors
- One-hit deaths: Standard for arcade shooters of the time, demanding precision
- Boss fights: Giant alien organisms that fill the screen

Cultural Impact and Legacy
- While it never gained the fame of R-Type, X Multiply earned a cult following among hardcore shmup fans
- Its tentacle system was seen as a spiritual counterpart to R-Type's Force Pod
- The game was later included in the R-Type Dimensions EX compilation (2019)
- Strong influence on future bio-mechanical design aesthetics in shoot 'em ups

Fun Facts
- The grotesque visual style was inspired by H.R. Giger and 1980s sci-fi horror films
- The game is often paired with Image Fight in retro collections, showcasing Irem’s shooter legacy
- Despite being a Japan-only release in arcades, X Multiply gained international attention through emulation and re-releases

Conclusion
X Multiply may not have achieved the iconic status of R-Type, but its unique mechanics and disturbing visual flair cemented its place in arcade shooter history. With its blend of biological horror and innovative gameplay, it remains a cult classic worth revisiting.