Games like Jet Set Knights
Games like Jet Set Knights include Broforce, Duck Game, TowerFall Ascension, Cuphead, and Shovel Knight: Treasure Trove. We matched them by the tags players give Jet Set Knights on Steam (Platformer, Tower Defense, Action, Local Co-Op, and Local Multiplayer): closest matches first, and among equally close ones the better-known games.

Broforce
Shared: Action · Platformer · Local Co-Op

Duck Game
Shared: Action · Local Multiplayer · Platformer

TowerFall Ascension
Shared: Local Multiplayer · Action · Platformer

Cuphead
Shared: Platformer · Local Co-Op · Indie

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

Katana ZERO
Shared: Action · Platformer · Pixel Graphics

Super Meat Boy
Shared: Platformer · Indie · Pixel Graphics

Celeste
Shared: Platformer · Pixel Graphics · Indie

SANABI
Shared: Action · Pixel Graphics · Platformer

Rivals of Aether
Shared: Platformer · Local Multiplayer · Pixel Graphics

Spelunky 2
Shared: Platformer · 2D Platformer · Local Co-Op

Pizza Tower
Shared: Platformer · Indie · 2D Platformer

Skul: The Hero Slayer
Shared: Action · Indie · Platformer

Brawlhalla
Shared: Platformer · Local Multiplayer · 2D Platformer

Rayman® Legends
Shared: Platformer · Action · Local Co-Op

UFO 50
Shared: Action · Indie · Pixel Graphics

Move or Die
Shared: Action · Local Multiplayer · Platformer

Risk of Rain (2013)
Shared: Platformer · Action · Indie

Spelunky
Shared: Platformer · Local Co-Op · Indie

Door Kickers: Action Squad
Shared: Local Co-Op · Action · Pixel Graphics

SpeedRunners
Shared: Local Multiplayer · Platformer · Indie

The Messenger
Shared: Platformer · Pixel Graphics · Action

BattleBlock Theater®
Shared: Platformer · Local Co-Op · Local Multiplayer

Downwell
Shared: Platformer · Pixel Graphics · Indie