Games like FIREBALL
Games like FIREBALL include Celeste, Super Meat Boy, Geometry Dash, SANABI, and VVVVVV. We matched them by the tags players give FIREBALL on Steam (Precision Platformer, 2D Platformer, Difficult, Platformer, and 2D): closest matches first, and among equally close ones the better-known games.

Celeste
Shared: Precision Platformer · Difficult · 2D Platformer

Super Meat Boy
Shared: Precision Platformer · Difficult · Platformer

Geometry Dash
Shared: Difficult · Precision Platformer · 2D

SANABI
Shared: 2D Platformer · Cyberpunk · Action

VVVVVV
Shared: Precision Platformer · Platformer · 2D Platformer

Katana ZERO
Shared: Platformer · 2D Platformer · Action

Hollow Knight
Shared: Platformer · Difficult · 2D

Downwell
Shared: Precision Platformer · Platformer · 2D Platformer

Jump King
Shared: Precision Platformer · Difficult · Platformer

Hollow Knight: Silksong
Shared: Difficult · 2D · Platformer

Spelunky 2
Shared: 2D Platformer · Platformer · Difficult

The End Is Nigh
Shared: Precision Platformer · Platformer · Difficult

Thomas Was Alone
Shared: Platformer · 2D Platformer · Precision Platformer

Super Meat Boy Forever
Shared: Difficult · Precision Platformer · Platformer

Nine Sols
Shared: Difficult · Platformer · 2D

Cuphead
Shared: Difficult · Platformer · 2D

Dustforce DX
Shared: Precision Platformer · Platformer · Difficult

Dungeon Escape
Shared: Precision Platformer · 2D Platformer · Difficult

BlazBlue Entropy Effect
Shared: 2D · Platformer · Action

N++ (NPLUSPLUS)
Shared: Precision Platformer · 2D Platformer · Difficult

Pizza Tower
Shared: 2D Platformer · Platformer · 2D

Ambidextro
Shared: Precision Platformer · 2D Platformer · Action

Rain World
Shared: Difficult · Platformer · 2D

Alex Kidd in Miracle World DX
Shared: Precision Platformer · 2D Platformer · Difficult