Games like Box Ninja
Games like Box Ninja include Braid, FEZ, LIMBO, Defy Gravity Extended, and Portal 2. We matched them by the tags players give Box Ninja on Steam (Casual, 2D, Platformer, Puzzle, and 2D Platformer): closest matches first, and among equally close ones the better-known games.

Braid
Shared: Puzzle · Puzzle Platformer · Platformer

FEZ
Shared: Platformer · Puzzle · Casual

LIMBO
Shared: Platformer · Puzzle · Puzzle Platformer

Defy Gravity Extended
Shared: Platformer · Puzzle Platformer · Puzzle

Portal 2
Shared: Platformer · Puzzle · Singleplayer

Celeste
Shared: Platformer · Pixel Graphics · 2D Platformer

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

Laughing to Die
Shared: Casual · Platformer · Puzzle

Öoo
Shared: Puzzle Platformer · Puzzle · 2D Platformer

Trine 2: Complete Story
Shared: Platformer · Puzzle Platformer · 2D Platformer

ANIMAL WELL
Shared: Puzzle · Platformer · 2D

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

Squishy the Suicidal Pig
Shared: Platformer · Puzzle · Puzzle Platformer

PICO PARK
Shared: Casual · Puzzle Platformer · Platformer

The Messenger
Shared: Platformer · 2D · Pixel Graphics

Out There Somewhere
Shared: Platformer · Puzzle · 2D

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

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

KarmaZoo
Shared: Casual · Platformer · Puzzle

Moonleap
Shared: Platformer · Puzzle · Puzzle Platformer

ElecHead
Shared: Platformer · Puzzle · Puzzle Platformer

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

Nihilumbra
Shared: Platformer · Casual · Puzzle

Evan's Remains
Shared: Casual · Puzzle Platformer · Platformer