Games like Smoking Gun
Games like Smoking Gun include BALL x PIT, Sky Force Reloaded, LUFTRAUSERS, Vampire Survivors, and Planes, Bullets and Vodka. We matched them by the tags players give Smoking Gun on Steam (Shoot 'Em Up, Bullet Hell, Arcade, Top-Down Shooter, and Western): closest matches first, and among equally close ones the better-known games.

BALL x PIT
Shared: Arcade · Bullet Hell · Action

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

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

Vampire Survivors
Shared: Bullet Hell · Singleplayer · Indie

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

UBERMOSH Vol.5
Shared: Arcade · Action · Bullet Hell

20 Minutes Till Dawn
Shared: Bullet Hell · Shoot 'Em Up · Top-Down Shooter

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

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

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

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

Cyberhunt
Shared: Shoot 'Em Up · Action · Indie

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

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

Megabonk
Shared: Bullet Hell · Indie · Action

Hotline Miami
Shared: Action · Indie · Violent

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

Bit Blaster XL
Shared: Shoot 'Em Up · Bullet Hell · Arcade

Exit the Gungeon
Shared: Arcade · Bullet Hell · Action

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

Touhou Tenkuushou ~ Hidden Star in Four Seasons.
Shared: Bullet Hell · Shoot 'Em Up · Arcade

Nex Machina
Shared: Bullet Hell · Arcade · Shoot 'Em Up

DoDonPachi Resurrection
Shared: Shoot 'Em Up · Bullet Hell · Top-Down Shooter

Hotline Miami 2: Wrong Number
Shared: Action · Violent · Retro