Games like Polygon Attack
Games like Polygon Attack include Cyberhunt, Planes, Bullets and Vodka, Bit Blaster XL, Chorus, and Star Saviors. We matched them by the tags players give Polygon Attack on Steam (Indie, Casual, Action, Space, and Arcade): closest matches first, and among equally close ones the better-known games.

Cyberhunt
Shared: Indie · Casual · Action

Planes, Bullets and Vodka
Shared: Casual · Action · Arcade

Bit Blaster XL
Shared: Arcade · Shooter · Action

Chorus
Shared: Indie · Action · Space

Star Saviors
Shared: Indie · Action · Space

Waveform
Shared: Indie · Casual · Arcade

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

Exit the Gungeon
Shared: Indie · Action · Arcade

LUFTRAUSERS
Shared: Indie · Action · Arcade

Deliver Us The Moon
Shared: Indie · Action · Adventure

Vampire Survivors
Shared: Indie · Casual · Bullet Hell

TouHou Makuka Sai ~ Fantastic Danmaku Festival
Shared: Indie · Action · Casual

Ikaruga
Shared: Action · Arcade · Shoot 'Em Up

Sun Blast: Star Fighter
Shared: Indie · Action · Adventure

Halo: Spartan Assault
Shared: Action · Singleplayer · Shooter

BEEP
Shared: Indie · Adventure · Action

Starblast
Shared: Action · Indie · Space

Defy Gravity Extended
Shared: Indie · Space · Action

ZeroRanger
Shared: Indie · Action · Shoot 'Em Up

STAR WARS™ Battlefront™ II
Shared: Space · Shooter · Action

Distant Space
Shared: Indie · Space · Arcade

Hotline Miami
Shared: Indie · Action · Top-Down

Zombotron
Shared: Action · Indie · Adventure

Caster
Shared: Indie · Action · Casual