Games like The Last Hearth
Games like The Last Hearth include Rain World, Terraria, Hollow Knight, ANIMAL WELL, and Hollow Knight: Silksong. We matched them by the tags players give The Last Hearth on Steam (Adventure, Platformer, Side Scroller, Exploration, and 2D): closest matches first, and among equally close ones the better-known games.

Rain World
Shared: Exploration · Platformer · Atmospheric

Terraria
Shared: Adventure · 2D · Pixel Graphics

Hollow Knight
Shared: Platformer · 2D · Exploration

ANIMAL WELL
Shared: Exploration · Platformer · Pixel Graphics

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

FEZ
Shared: Platformer · Exploration · Adventure

LIMBO
Shared: Platformer · Adventure · 2D

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

GRIS
Shared: Adventure · Platformer · Atmospheric

SANABI
Shared: Adventure · Pixel Graphics · 2D

Reventure
Shared: Adventure · Platformer · Pixel Graphics

Jusant
Shared: Adventure · Exploration · Cinematic

Celeste
Shared: Platformer · Pixel Graphics · Adventure

Dead Cells
Shared: Adventure · 2D · Pixel Graphics

Axiom Verge
Shared: Platformer · Pixel Graphics · Adventure

Haiku, the Robot
Shared: Adventure · Exploration · Platformer

FAR: Lone Sails
Shared: Adventure · Exploration · Atmospheric

Deadlight
Shared: Platformer · Adventure · Side Scroller

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

DAVE THE DIVER
Shared: Adventure · Pixel Graphics · Exploration

A Short Hike
Shared: Adventure · Exploration · Pixel Graphics

Five Nights at Freddy's: Into the Pit
Shared: Adventure · 2D · Pixel Graphics

Momodora: Reverie Under The Moonlight
Shared: Side Scroller · Exploration · Pixel Graphics

The Final Station
Shared: Adventure · Pixel Graphics · 2D