Games like Arm of Satan: Chapter 1
Games like Arm of Satan: Chapter 1 include Celeste, Geometry Dash, Super Meat Boy, Momodora: Reverie Under The Moonlight, and SANABI. We matched them by the tags players give Arm of Satan: Chapter 1 on Steam (Precision Platformer, Side Scroller, 2D Platformer, Difficult, and Platformer): closest matches first, and among equally close ones the better-known games.

Celeste
Shared: Precision Platformer · Difficult · 2D Platformer

Geometry Dash
Shared: Difficult · Precision Platformer · 2D

Super Meat Boy
Shared: Precision Platformer · Difficult · Platformer

Momodora: Reverie Under The Moonlight
Shared: Side Scroller · 2D Platformer · Female Protagonist

SANABI
Shared: 2D Platformer · Story Rich · 2D

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

Downwell
Shared: Precision Platformer · Platformer · 2D Platformer

Hollow Knight
Shared: Platformer · Difficult · 2D

Rogue Legacy 2
Shared: Arcade · Platformer · Difficult

Afterimage
Shared: 2D Platformer · Side Scroller · Female Protagonist

Thomas Was Alone
Shared: Side Scroller · Precision Platformer · Platformer

VVVVVV
Shared: Precision Platformer · 2D Platformer · Platformer

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

Jump King
Shared: Precision Platformer · Difficult · Platformer

Will You Snail?
Shared: Precision Platformer · Difficult · 2D Platformer

Spelunky 2
Shared: 2D Platformer · Platformer · Difficult

Bō: Path of the Teal Lotus
Shared: Precision Platformer · Side Scroller · 2D Platformer

Pepper Grinder
Shared: 2D Platformer · Difficult · Platformer

Blasphemous 2
Shared: Difficult · 2D Platformer · Side Scroller

Bread & Fred
Shared: 2D Platformer · Precision Platformer · Difficult

Katana ZERO
Shared: Platformer · 2D Platformer · Story Rich

Wings of Vi
Shared: Precision Platformer · Difficult · Platformer

Nine Sols
Shared: Difficult · Platformer · 2D

Laika: Aged Through Blood
Shared: 2D Platformer · Arcade · Platformer