Games like Earth Atlantis
Games like Earth Atlantis include My Friend Pedro, LUFTRAUSERS, Touhou Koumakyou: New Classic - the Embodiment of Scarlet Devil, Hotline Miami, and Zombotron. We matched them by the tags players give Earth Atlantis on Steam (Indie, Action, Shoot 'Em Up, Side Scroller, and Bullet Hell): closest matches first, and among equally close ones the better-known games.

My Friend Pedro
Shared: Indie · Action · Shooter

LUFTRAUSERS
Shared: Indie · Action · Bullet Hell

Touhou Koumakyou: New Classic - the Embodiment of Scarlet Devil
Shared: Shoot 'Em Up · Bullet Hell · Action

Hotline Miami
Shared: Action · Indie · Great Soundtrack

Zombotron
Shared: Action · Indie · Singleplayer

ZeroRanger
Shared: Indie · Shoot 'Em Up · Action

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

Cuphead
Shared: Indie · Bullet Hell · Difficult

Hollow Knight: Silksong
Shared: Indie · Singleplayer · Great Soundtrack

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

Hollow Knight
Shared: Indie · Singleplayer · Great Soundtrack

Touhou Kouryudou ~ Unconnected Marketeers.
Shared: Action · Shoot 'Em Up · Bullet Hell

DRAINUS
Shared: Action · Indie · Shoot 'Em Up

Shovel Knight: Treasure Trove
Shared: Indie · Action · Retro

Hotline Miami 2: Wrong Number
Shared: Action · Indie · Great Soundtrack

Exit the Gungeon
Shared: Indie · Action · Bullet Hell

Jets'n'Guns 2
Shared: Indie · Action · Shoot 'Em Up

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

SANABI
Shared: Action · Indie · Singleplayer

Seen
Shared: Indie · Singleplayer · Action

TouHou Makuka Sai ~ Fantastic Danmaku Festival Part II
Shared: Indie · Shoot 'Em Up · Bullet Hell

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

Devil Daggers
Shared: Indie · Action · Shooter

Hyper Light Drifter
Shared: Indie · Action · Atmospheric