Games like NEONomicon
Games like NEONomicon include Defy Gravity Extended, LIMBO, Broforce, Skul: The Hero Slayer, and Hollow Knight. We matched them by the tags players give NEONomicon on Steam (Indie, Action, Platformer, Casual, and Puzzle Platformer): closest matches first, and among equally close ones the better-known games.

Defy Gravity Extended
Shared: Indie · Platformer · Puzzle Platformer

LIMBO
Shared: Indie · Puzzle Platformer · Platformer

Broforce
Shared: Action · Platformer · Indie

Skul: The Hero Slayer
Shared: Indie · Action · 2D

Hollow Knight
Shared: Platformer · Indie · 2D

Pikuniku
Shared: Indie · Casual · Action

Dust: An Elysian Tail
Shared: Action · Platformer · Indie

Planet of Lana
Shared: Action · Puzzle Platformer · Platformer

Nihilumbra
Shared: Indie · Platformer · Casual

BEEP
Shared: Indie · Platformer · 2D

Minimalism
Shared: Indie · Action · Casual

Rogue Legacy
Shared: Indie · Platformer · Action

Katana ZERO
Shared: Action · Platformer · Indie

PICO PARK
Shared: Puzzle Platformer · Casual · Platformer

MO:Astray
Shared: Indie · Action · Platformer

Super Fancy Pants Adventure
Shared: Action · Indie · Platformer

Braid
Shared: Indie · Puzzle Platformer · Platformer

SpeedRunners
Shared: Indie · Platformer · Action

FEZ
Shared: Indie · Platformer · Casual

BADLAND: Game of the Year Edition
Shared: Indie · Action · 2D

BlazBlue Entropy Effect
Shared: Action · Platformer · 2D

Hollow Knight: Silksong
Shared: Indie · Platformer · 2D

Toki Tori
Shared: Indie · Platformer · Casual

Out There Somewhere
Shared: Indie · Platformer · Action