Games like Beholder's Lair
Games like Beholder's Lair include Celeste, SANABI, Super Meat Boy, Jump King, and VVVVVV. We matched them by the tags players give Beholder's Lair on Steam (Precision Platformer, Action, Perma Death, Dark Fantasy, and Pixel Graphics): closest matches first, and among equally close ones the better-known games.

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

SANABI
Shared: Action · Pixel Graphics · Adventure

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

Jump King
Shared: Precision Platformer · Pixel Graphics · Action

VVVVVV
Shared: Precision Platformer · Pixel Graphics · 2D Platformer

Downwell
Shared: Precision Platformer · Pixel Graphics · Action

Blasphemous
Shared: Dark Fantasy · Pixel Graphics · Action

Katana ZERO
Shared: Action · Pixel Graphics · 2D Platformer

Skul: The Hero Slayer
Shared: Action · Pixel Graphics · Indie

Ambidextro
Shared: Precision Platformer · Action · Dark Fantasy

The End Is Nigh
Shared: Precision Platformer · Action · Adventure

Shovel Knight: Treasure Trove
Shared: Pixel Graphics · Action · Platformer

Dead Cells
Shared: Adventure · Pixel Graphics · Action

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

Owlboy
Shared: Pixel Graphics · Adventure · Action

Dust: An Elysian Tail
Shared: Action · Adventure · Platformer

Bloodstained: Curse of the Moon
Shared: Action · Pixel Graphics · Platformer

Sonic Origins
Shared: Action · Adventure · 2D Platformer

Blasphemous 2
Shared: Fantasy · Adventure · Pixel Graphics

Broforce
Shared: Action · Pixel Graphics · Platformer

Hollow Knight
Shared: Platformer · Singleplayer · Adventure

Deaths Gambit: Afterlife
Shared: Pixel Graphics · Action · Dark Fantasy

Rogue Legacy
Shared: Action · Platformer · Singleplayer

MO:Astray
Shared: Action · Pixel Graphics · Adventure