Games like Deepworld
Games like Deepworld include Terraria, Rust, Once Human, Last Oasis, and Albion Online. We matched them by the tags players give Deepworld on Steam (Free to Play, Massively Multiplayer, 2D, Adventure, and Sandbox): closest matches first, and among equally close ones the better-known games.
Terraria
Shared: Sandbox · 2D · Adventure
Rust
Shared: Sandbox · Adventure · Survival
Once Human
Shared: Free to Play · Action · Survival
Last Oasis
Shared: Massively Multiplayer · Adventure · Action
Albion Online
Shared: Free to Play · Massively Multiplayer · Sandbox
Transformice
Shared: Free to Play · Massively Multiplayer · 2D
ARK: Survival Evolved
Shared: Adventure · Survival · Sandbox
VRChat
Shared: Free to Play · Massively Multiplayer · Early Access
Neverwinter
Shared: Free to Play · Massively Multiplayer · Adventure
RPG MO
Shared: Free to Play · Massively Multiplayer · RPG
Don't Starve Together
Shared: Adventure · Survival · Sandbox
Marvel Rivals
Shared: Free to Play · Action · Massively Multiplayer
Starbound
Shared: Sandbox · Adventure · Survival
ARK: Survival Ascended
Shared: Adventure · Survival · Sandbox
Trove
Shared: Free to Play · Sandbox · RPG
Elsword
Shared: Free to Play · Massively Multiplayer · Adventure
Portal Knights
Shared: Adventure · Sandbox · RPG
Conan Exiles Enhanced
Shared: Massively Multiplayer · Sandbox · Survival
PixARK
Shared: Adventure · Massively Multiplayer · Sandbox
Touhou Big Big Battle
Shared: Massively Multiplayer · Early Access · Free to Play
Forager
Shared: 2D · Sandbox · Adventure
Warframe
Shared: Free to Play · Massively Multiplayer · Action
Mortal Online
Shared: Free to Play · Massively Multiplayer · Sandbox
Dark and Light
Shared: Massively Multiplayer · Sandbox · Adventure