Games like Piko Piko
Games like Piko Piko include Momodora: Reverie Under The Moonlight, Hollow Knight: Silksong, Rabi-Ribi, Record of Lodoss War-Deedlit in Wonder Labyrinth-, and Hollow Knight. We matched them by the tags players give Piko Piko on Steam (Metroidvania, 2D Platformer, Pixel Graphics, Exploration, and Platformer): closest matches first, and among equally close ones the better-known games.

Momodora: Reverie Under The Moonlight
Shared: Metroidvania · 2D Platformer · Pixel Graphics

Hollow Knight: Silksong
Shared: Metroidvania · Platformer · Exploration

Rabi-Ribi
Shared: Metroidvania · Pixel Graphics · Exploration

Record of Lodoss War-Deedlit in Wonder Labyrinth-
Shared: Metroidvania · Exploration · Female Protagonist

Hollow Knight
Shared: Metroidvania · Platformer · Exploration

Celeste
Shared: Pixel Graphics · 2D Platformer · Platformer

Webbed
Shared: 2D Platformer · Pixel Graphics · Cute

Nyaruru Fishy Fight
Shared: Metroidvania · 2D Platformer · Exploration

The Messenger
Shared: Metroidvania · Pixel Graphics · Platformer

Afterimage
Shared: Metroidvania · 2D Platformer · Female Protagonist

Rain World
Shared: Exploration · Pixel Graphics · Platformer

ANIMAL WELL
Shared: Metroidvania · Exploration · Pixel Graphics

Shantae and the Seven Sirens
Shared: Metroidvania · Female Protagonist · Platformer

Öoo
Shared: Metroidvania · 2D Platformer · Exploration

Ori and the Will of the Wisps
Shared: Metroidvania · Platformer · Exploration

Pizza Tower
Shared: 2D Platformer · Pixel Graphics · Platformer

Lost Ruins
Shared: Metroidvania · Pixel Graphics · Platformer

Shantae and the Pirate's Curse
Shared: Metroidvania · Platformer · Pixel Graphics

Owlboy
Shared: Pixel Graphics · Metroidvania · Platformer

Gato Roboto
Shared: Metroidvania · Pixel Graphics · Platformer

UnEpic
Shared: Metroidvania · Platformer · Exploration

Bloodstained: Ritual of the Night
Shared: Metroidvania · Female Protagonist · Platformer

Timespinner
Shared: Metroidvania · 2D Platformer · Female Protagonist

Shantae: Risky's Revenge - Director's Cut
Shared: Metroidvania · Platformer · Pixel Graphics