Games like Mantle
Games like Mantle include Papers, Please, Your Only Move Is HUSTLE, Into the Breach, Undertale, and OneShot. We matched them by the tags players give Mantle on Steam (Turn-Based Strategy, Story Rich, 2D, Superhero, and Simulation): closest matches first, and among equally close ones the better-known games.

Papers, Please
Shared: Simulation · Pixel Graphics · Story Rich

Your Only Move Is HUSTLE
Shared: Turn-Based Strategy · 2D · Pixel Graphics

Into the Breach
Shared: Turn-Based Strategy · Pixel Graphics · Strategy

Undertale
Shared: Story Rich · Pixel Graphics · 2D

OneShot
Shared: Story Rich · Pixel Graphics · 2D

The Talos Principle
Shared: Story Rich · Puzzle · Sci-fi

OMORI
Shared: Story Rich · Pixel Graphics · 2D

Mewgenics
Shared: Turn-Based Strategy · 2D · Turn-Based Tactics

The Escapists
Shared: 2D · Pixel Graphics · Simulation

Super Robot Wars 30
Shared: Turn-Based Strategy · Simulation · 2D

Detroit: Become Human
Shared: Story Rich · Robots · Multiple Endings

STAR WARS Zero Company™
Shared: Turn-Based Strategy · Sci-fi · Turn-Based Tactics

DELTARUNE
Shared: Story Rich · Pixel Graphics · 2D

Death and Taxes
Shared: Story Rich · Simulation · Multiple Endings

There Is No Game: Wrong Dimension
Shared: Story Rich · Pixel Graphics · Puzzle

No Umbrellas Allowed
Shared: Simulation · Story Rich · Pixel Graphics

The Test
Shared: Story Rich · Simulation · Pixel Graphics

Wolfstride
Shared: Story Rich · Turn-Based Strategy · Robots

Ib
Shared: Story Rich · 2D · Pixel Graphics

Tactical Breach Wizards
Shared: Story Rich · Turn-Based Strategy · Puzzle

Symphony of War: The Nephilim Saga
Shared: Story Rich · Turn-Based Strategy · Pixel Graphics

BattleTech
Shared: Turn-Based Strategy · Robots · Sci-fi

Lucy -The Eternity She Wished For-
Shared: Story Rich · Robots · Simulation

Rhythm Doctor
Shared: Story Rich · Pixel Graphics · 2D