Games like 1x! Space Adventure
Games like 1x! Space Adventure include BALL x PIT, Sky Force Reloaded, Bit Blaster XL, LUFTRAUSERS, and Planes, Bullets and Vodka. We matched them by the tags players give 1x! Space Adventure on Steam (Action, Arcade, Shooter, Bullet Hell, and Shoot 'Em Up): closest matches first, and among equally close ones the better-known games.

BALL x PIT
Shared: Action · Arcade · Bullet Hell

Sky Force Reloaded
Shared: Arcade · Shoot 'Em Up · Bullet Hell

Bit Blaster XL
Shared: Bullet Hell · Shooter · Arcade

LUFTRAUSERS
Shared: Arcade · Action · Bullet Hell

Planes, Bullets and Vodka
Shared: Action · Shoot 'Em Up · Arcade

Nova Drift
Shared: Arcade · Bullet Hell · Shoot 'Em Up

Revolution Ace
Shared: Action · Shoot 'Em Up · Bullet Hell

Star Saviors
Shared: Action · Bullet Hell · Shoot 'Em Up

Vampire Survivors
Shared: Bullet Hell · 2D · Arcade

Ikaruga
Shared: Arcade · Bullet Hell · Action

DoDonPachi Resurrection
Shared: Shooter · Bullet Hell · Arcade

ZeroRanger
Shared: Action · Shoot 'Em Up · Bullet Hell

Cyberhunt
Shared: Action · Arcade · Shoot 'Em Up

Exit the Gungeon
Shared: Arcade · Action · Bullet Hell

DRAINUS
Shared: Action · Shooter · Shoot 'Em Up

Crimzon Clover World EXplosion
Shared: Action · Arcade · Bullet Hell

12 is Better Than 6
Shared: Action · Shooter · Top-Down Shooter

Touhou Kinjoukyou ~ Fossilized Wonders.
Shared: Action · Bullet Hell · Shooter

Chippy
Shared: Bullet Hell · Shoot 'Em Up · Arcade

Beat Hazard
Shared: Bullet Hell · Shoot 'Em Up · Action

BLUE REVOLVER
Shared: Action · Bullet Hell · Shoot 'Em Up

Halo: Spartan Assault
Shared: Action · Top-Down Shooter · Shooter

Waves
Shared: Bullet Hell · Shooter · Arcade

Nex Machina
Shared: Action · Arcade · Bullet Hell