Games like THEMIS
Games like THEMIS include Portal 2, LIMBO, Portal, Little Nightmares, and COCOON. We matched them by the tags players give THEMIS on Steam (Puzzle Platformer, Puzzle, Adventure, Platformer, and 3D): closest matches first, and among equally close ones the better-known games.

Portal 2
Shared: Puzzle · Platformer · Puzzle Platformer

LIMBO
Shared: Puzzle Platformer · Puzzle · Platformer

Portal
Shared: Puzzle Platformer · Puzzle · Sci-fi

Little Nightmares
Shared: Adventure · Puzzle Platformer · Puzzle

COCOON
Shared: Puzzle · Adventure · Puzzle Platformer

The Pedestrian
Shared: Puzzle Platformer · Puzzle · Platformer

Mind Over Magnet
Shared: Puzzle Platformer · Puzzle · Adventure

Human Fall Flat
Shared: Puzzle · Adventure · Puzzle Platformer

Defy Gravity Extended
Shared: Puzzle Platformer · Puzzle · Platformer

FEZ
Shared: Puzzle · Platformer · Adventure

The Talos Principle 2
Shared: Puzzle · Puzzle Platformer · Sci-fi

Viewfinder
Shared: Puzzle Platformer · Puzzle · Adventure

Out There Somewhere
Shared: Platformer · Puzzle · Adventure

Chained Together
Shared: Adventure · Platformer · Puzzle Platformer

Little Nightmares II
Shared: Adventure · Puzzle · Puzzle Platformer

Seen
Shared: Adventure · Puzzle · Platformer

Supraland
Shared: Puzzle Platformer · Adventure · Puzzle

Oddworld: New 'n' Tasty
Shared: Puzzle Platformer · Adventure · Platformer

Contrast
Shared: Adventure · Puzzle · Platformer

Murders on the Yangtze River
Shared: Puzzle · Adventure · Puzzle Platformer

ElecHead
Shared: Puzzle Platformer · Puzzle · Platformer

INSIDE
Shared: Puzzle Platformer · Adventure · Puzzle

Planet of Lana
Shared: Puzzle Platformer · Puzzle · Platformer

Monument Valley
Shared: Puzzle · Adventure · Puzzle Platformer