Games like Iridescent
Games like Iridescent include Minecraft Dungeons, ANIMAL WELL, LIMBO, Lost Castle, and The Slormancer. We matched them by the tags players give Iridescent on Steam (Side Scroller, Action-Adventure, Dungeon Crawler, Hack and Slash, and Exploration): closest matches first, and among equally close ones the better-known games.

Minecraft Dungeons
Shared: Dungeon Crawler · Hack and Slash · Action-Adventure

ANIMAL WELL
Shared: Exploration · Puzzle · Puzzle Platformer

LIMBO
Shared: Puzzle Platformer · Puzzle · Side Scroller

Lost Castle
Shared: Side Scroller · Dungeon Crawler · Hack and Slash

The Slormancer
Shared: Dungeon Crawler · Hack and Slash · Action-Adventure

Minecraft Dungeons II
Shared: Dungeon Crawler · Action-Adventure · Hack and Slash

STAR WARS Jedi: Fallen Order™
Shared: Action-Adventure · Exploration · Puzzle

Skul: The Hero Slayer
Shared: Side Scroller · Pixel Graphics · 2D

Murders on the Yangtze River
Shared: Puzzle · Exploration · Puzzle Platformer

Dungeons of Hinterberg
Shared: Exploration · Dungeon Crawler · Puzzle

Öoo
Shared: Puzzle Platformer · Exploration · Puzzle

Chronicon
Shared: Dungeon Crawler · Hack and Slash · Action-Adventure

Wizard with a Gun
Shared: Action-Adventure · Dungeon Crawler · Exploration

ICEY
Shared: Side Scroller · Hack and Slash · Action

SANABI
Shared: Action-Adventure · Pixel Graphics · Action

The Happyhills Homicide 2: Out For Blood
Shared: Action-Adventure · Side Scroller · Exploration

Anomaly Agent
Shared: Side Scroller · Hack and Slash · Action-Adventure

BlazBlue Entropy Effect
Shared: Action-Adventure · 2D · Hack and Slash

Touhou Luna Nights
Shared: Side Scroller · Exploration · Action-Adventure

Regions Of Ruin
Shared: Hack and Slash · Side Scroller · Dungeon Crawler

Afterimage
Shared: Side Scroller · Exploration · Hack and Slash

Deaths Door
Shared: Action-Adventure · Hack and Slash · Exploration

FEZ
Shared: Exploration · Puzzle · Pixel Graphics

Moonlighter
Shared: Hack and Slash · Dungeon Crawler · Pixel Graphics