Games like PEPPERED: an existential platformer
Games like PEPPERED: an existential platformer include Celeste, Undertale, OneShot, SANABI, and Detroit: Become Human. We matched them by the tags players give PEPPERED: an existential platformer on Steam (Story Rich, Pixel Graphics, Difficult, Replay Value, and Precision Platformer): closest matches first, and among equally close ones the better-known games.

Celeste
Shared: Pixel Graphics · Difficult · Precision Platformer

Undertale
Shared: Story Rich · Pixel Graphics · Choices Matter

OneShot
Shared: Story Rich · Pixel Graphics · Singleplayer

SANABI
Shared: Story Rich · Pixel Graphics · Singleplayer

Detroit: Become Human
Shared: Story Rich · Choices Matter · Singleplayer

The Binding of Isaac: Rebirth
Shared: Replay Value · Difficult · Pixel Graphics

Papers, Please
Shared: Pixel Graphics · Story Rich · Singleplayer

The Test
Shared: Story Rich · Pixel Graphics · Singleplayer

Portal 2
Shared: Story Rich · Singleplayer · Dark Humor

The Red Strings Club
Shared: Pixel Graphics · Story Rich · Choices Matter

To the Moon
Shared: Story Rich · Pixel Graphics · Singleplayer

Jump King
Shared: Difficult · Pixel Graphics · Precision Platformer

Super Meat Boy
Shared: Difficult · Precision Platformer · Pixel Graphics

The Witcher 3: Wild Hunt — Remastered
Shared: Story Rich · Singleplayer · Choices Matter

Hollow Knight
Shared: Difficult · Singleplayer · Story Rich

INMOST
Shared: Pixel Graphics · Story Rich · Psychological

Yes, Your Grace
Shared: Pixel Graphics · Story Rich · Choices Matter

Changed
Shared: Difficult · Pixel Graphics · Singleplayer

Hollow Knight: Silksong
Shared: Difficult · Singleplayer · Indie

Getting Over It with Bennett Foddy
Shared: Difficult · Singleplayer · Replay Value

Back to the Dawn
Shared: Pixel Graphics · Story Rich · Choices Matter

Finding Paradise
Shared: Story Rich · Pixel Graphics · Singleplayer

DELTARUNE
Shared: Story Rich · Pixel Graphics · Singleplayer

Martial Law
Shared: Pixel Graphics · Story Rich · Choices Matter