Games like Flat Earths!
Games like Flat Earths! include Overcooked, Overcooked! 2, Timberman VS, Timberman, and Move or Die. We matched them by the tags players give Flat Earths! on Steam (Action, Indie, Casual, 4 Player Local, and Arcade): closest matches first, and among equally close ones the better-known games.

Overcooked
Shared: Indie · Local Co-Op · Arcade

Overcooked! 2
Shared: Local Co-Op · Casual · 4 Player Local

Timberman VS
Shared: Action · Casual · Indie

Timberman
Shared: Casual · Indie · Action

Move or Die
Shared: Action · Indie · 4 Player Local

Vampire Survivors
Shared: Indie · Casual · Action

Stick Fight: The Game
Shared: Action · 4 Player Local · Casual

Streets of Rage 4
Shared: Action · Indie · Arcade

Gang Beasts
Shared: Action · Casual · Indie

Moving Out
Shared: Action · Casual · Indie

Broforce
Shared: Action · Indie · Local Co-Op

Twin Shot Deluxe
Shared: Action · Casual · Arcade

PARTICLE MACE
Shared: Action · Indie · Arcade

A Few Quick Matches
Shared: Indie · Casual · Action

TowerFall Ascension
Shared: Indie · Action · Local Co-Op

Chicken Invaders 5
Shared: Action · Indie · Casual

The TakeOver
Shared: Action · Indie · Casual

SpeedRunners
Shared: Indie · Action · 4 Player Local

Cyberhunt
Shared: Action · Indie · Casual

Hidden in Plain Sight
Shared: 4 Player Local · Casual · Indie

Snakeybus
Shared: Indie · Action · Casual

One Finger Death Punch 2
Shared: Action · Indie · Casual

Unrailed!
Shared: Casual · Action · Local Co-Op

Pikuniku
Shared: Indie · Casual · Action