Games like Into The Sky
Games like Into The Sky include Portal, Portal 2, Refunct, Clustertruck, and Defy Gravity Extended. We matched them by the tags players give Into The Sky on Steam (Action, Puzzle Platformer, Casual, Parkour, and 3D Platformer): closest matches first, and among equally close ones the better-known games.

Portal
Shared: Puzzle Platformer · 3D Platformer · Puzzle

Portal 2
Shared: Platformer · Puzzle Platformer · Puzzle

Refunct
Shared: Parkour · 3D Platformer · Puzzle Platformer

Clustertruck
Shared: Action · Parkour · 3D Platformer

Defy Gravity Extended
Shared: Puzzle Platformer · Platformer · Action

Mirror's Edge™ Catalyst
Shared: Parkour · Action · 3D Platformer

A Story About My Uncle
Shared: Parkour · Platformer · 3D Platformer

LIMBO
Shared: Puzzle Platformer · Platformer · Puzzle

VHOLUME
Shared: Parkour · 3D Platformer · Casual

EDGE
Shared: Puzzle Platformer · Action · Puzzle

DeadCore
Shared: Action · Platformer · Parkour

Planet of Lana
Shared: Action · Puzzle Platformer · Platformer

Neon White
Shared: 3D Platformer · Action · Parkour

SEUM: Speedrunners from Hell
Shared: Parkour · 3D Platformer · Action

Mirror's Edge™
Shared: Parkour · 3D Platformer · Action

Haste
Shared: Parkour · Action · 3D Platformer

Shio
Shared: Action · Casual · Difficult

FrostRunner
Shared: Action · Parkour · 3D Platformer

Nihilumbra
Shared: Casual · Puzzle Platformer · Platformer

Braid
Shared: Puzzle Platformer · Puzzle · Platformer

Gorilla Tag
Shared: Parkour · Action · 3D Platformer

Toki Tori
Shared: Casual · Puzzle · Platformer

Climber Animals: Together
Shared: Casual · Puzzle Platformer · Platformer

Human Fall Flat
Shared: Puzzle Platformer · Puzzle · Action