Games like Ash and amber
Games like Ash and amber include Celeste, Braid, Webbed, Planet of Lana, and Vampire Survivors. We matched them by the tags players give Ash and amber on Steam (Casual, 2D Platformer, Puzzle Platformer, 2D, and Pixel Graphics): closest matches first, and among equally close ones the better-known games.

Celeste
Shared: Pixel Graphics · 2D Platformer · 2D

Braid
Shared: Puzzle Platformer · 2D Platformer · 2D

Webbed
Shared: 2D Platformer · Puzzle Platformer · Pixel Graphics

Planet of Lana
Shared: Puzzle Platformer · 2D Platformer · Female Protagonist

Vampire Survivors
Shared: Pixel Graphics · 2D · Casual

Öoo
Shared: Puzzle Platformer · 2D Platformer · 2D

FEZ
Shared: Pixel Graphics · Casual · Puzzle Platformer

SANABI
Shared: Pixel Graphics · 2D Platformer · 2D

Defy Gravity Extended
Shared: Puzzle Platformer · 2D · Casual

Laughing to Die
Shared: Casual · 2D Platformer · Puzzle Platformer

The Dark Queen of Mortholme
Shared: Casual · 2D · Pixel Graphics

OneShot
Shared: Pixel Graphics · Indie · Choices Matter

Munin
Shared: Casual · Puzzle Platformer · 2D Platformer

Undertale
Shared: Pixel Graphics · Choices Matter · 2D

Timberman
Shared: Casual · Pixel Graphics · 2D

Zup!
Shared: Casual · 2D · Puzzle Platformer

There Is No Game: Wrong Dimension
Shared: Casual · Pixel Graphics · Indie

LIMBO
Shared: Puzzle Platformer · 2D · Indie

Banana
Shared: Casual · 2D · Singleplayer

Zup! 2
Shared: Casual · 2D · Puzzle Platformer

Zup! F
Shared: Casual · 2D · Puzzle Platformer

Pizza Tower
Shared: 2D Platformer · Pixel Graphics · Indie

Unpacking
Shared: Casual · Pixel Graphics · Singleplayer

Super Meat Boy
Shared: 2D Platformer · Pixel Graphics · 2D