Games like Silk
Games like Silk include Terraria, Don't Starve Together, Don't Starve, Noita, and Rain World. We matched them by the tags players give Silk on Steam (Exploration, Sandbox, Survival, Trading, and Difficult): closest matches first, and among equally close ones the better-known games.

Terraria
Shared: Sandbox · Survival · Exploration

Don't Starve Together
Shared: Survival · Sandbox · Difficult

Don't Starve
Shared: Survival · Sandbox · Exploration

Noita
Shared: Sandbox · Roguelike · Difficult

Rain World
Shared: Exploration · Survival · Difficult

Core Keeper
Shared: Exploration · Survival · Sandbox

EVE Online
Shared: Exploration · Difficult · Trading

The Long Dark
Shared: Survival · Exploration · Sandbox

Valheim
Shared: Survival · Exploration · Open World

Starbound
Shared: Sandbox · Survival · Exploration

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

Stoneshard
Shared: Survival · Roguelike · RPG

Elin
Shared: Roguelike · Sandbox · RPG

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

Project Zomboid
Shared: Survival · Sandbox · Open World

Keplerth
Shared: Exploration · Sandbox · Survival

Kenshi
Shared: Sandbox · Survival · RPG

The Forest
Shared: Survival · Exploration · Open World

Dune: Awakening
Shared: Exploration · Survival · Sandbox

Forager
Shared: Survival · Sandbox · Pixel Graphics

Necesse
Shared: Sandbox · Survival · Open World

Conan Exiles Enhanced
Shared: Survival · Sandbox · Open World

Fallout 4
Shared: Exploration · RPG · Open World

Terminus: Zombie Survivors
Shared: Survival · Roguelike · Sandbox