Games like Guardian: Planet Defense
Games like Guardian: Planet Defense include Planes, Bullets and Vodka, Bit Blaster XL, Cyberhunt, LUFTRAUSERS, and Vampire Survivors. We matched them by the tags players give Guardian: Planet Defense on Steam (Action, Shoot 'Em Up, Casual, Shooter, and Arcade): closest matches first, and among equally close ones the better-known games.

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

Bit Blaster XL
Shared: Shoot 'Em Up · Shooter · Action

Cyberhunt
Shared: Action · Casual · Shoot 'Em Up

LUFTRAUSERS
Shared: Action · Arcade · Shoot 'Em Up

Vampire Survivors
Shared: 2D · Casual · Indie

Timberman
Shared: Casual · Action · Indie

DRAINUS
Shared: Action · Shoot 'Em Up · Shooter

Alex Jones: NWO Wars
Shared: Action · Shooter · Shoot 'Em Up

Revolution Ace
Shared: Action · Shoot 'Em Up · Shooter

A Dance of Fire and Ice
Shared: 2D · Arcade · Indie

Chicken Invaders 5
Shared: Action · Casual · Shoot 'Em Up

Geometry Wars: Retro Evolved
Shared: Casual · Arcade · Shoot 'Em Up

METAL SLUG
Shared: Action · Arcade · Shoot 'Em Up

Starblast
Shared: Action · Casual · Shoot 'Em Up

ShellShock Live
Shared: Action · 2D · Shooter

METAL SLUG X
Shared: Action · Arcade · Shoot 'Em Up

Broforce
Shared: Action · 2D · Shooter

Zombotron
Shared: Action · 2D · Shooter

State of Anarchy
Shared: Action · Casual · Shoot 'Em Up

Nova Drift
Shared: Shoot 'Em Up · Arcade · Shooter

ZeroRanger
Shared: Shoot 'Em Up · Action · Indie

Star Saviors
Shared: Shoot 'Em Up · Action · Arcade

BEEP
Shared: Action · Indie · 2D

BALL x PIT
Shared: Action · Arcade · Shoot 'Em Up