Games like Theo's World
Games like Theo's World include The Forest, Once Human, Terraria, Rust, and ARK: Survival Evolved. We matched them by the tags players give Theo's World on Steam (Adventure, Action, Racing, Building, and Exploration): closest matches first, and among equally close ones the better-known games.

The Forest
Shared: Adventure · Survival · Building

Once Human
Shared: Action · Open World · Building

Terraria
Shared: Adventure · Survival · Open World Survival Craft

Rust
Shared: Survival · Building · Adventure

ARK: Survival Evolved
Shared: Adventure · Survival · Building

Valheim
Shared: Building · Survival · Open World

Raft
Shared: Survival · Building · Adventure

Conan Exiles Enhanced
Shared: Building · Open World · Survival

Subnautica
Shared: Survival · Exploration · Open World

TerraTech
Shared: Building · Open World · Action

No Man's Sky
Shared: Open World · Exploration · Adventure

Stranded Deep
Shared: Adventure · Survival · Open World

My Time at Portia
Shared: Farming Sim · Open World · Adventure

Subnautica: Below Zero
Shared: Survival · Exploration · Open World

7 Days to Die
Shared: Survival · Open World · Building

Palworld
Shared: Open World · Survival · Adventure

Far Cry® Primal
Shared: Action · Adventure · Open World

Starbound
Shared: Adventure · Survival · Open World Survival Craft

Forager
Shared: Adventure · Survival · Farming Sim

Green Hell
Shared: Action · Survival · Open World

The Long Dark
Shared: Exploration · Adventure · Survival

Rise of the Tomb Raider™
Shared: Adventure · Action · Exploration

Core Keeper
Shared: Exploration · Open World · Survival

The Long Drive
Shared: Adventure · Open World · Exploration