Games like Beyond The Walls
Games like Beyond The Walls include Kingdom Two Crowns, Thronefall, Frostpunk, They Are Billions, and Age of Darkness: Final Stand. We matched them by the tags players give Beyond The Walls on Steam (Strategy, Tower Defense, 3D, Survival, and Base Building): closest matches first, and among equally close ones the better-known games.

Kingdom Two Crowns
Shared: Tower Defense · Strategy · Base Building

Thronefall
Shared: Strategy · Tower Defense · City Builder

Frostpunk
Shared: Strategy · Survival · City Builder

They Are Billions
Shared: Strategy · Base Building · Survival

Age of Darkness: Final Stand
Shared: Tower Defense · Strategy · Base Building

Manor Lords
Shared: Strategy · Base Building · City Builder

Foundation
Shared: Strategy · City Builder · Medieval

Factorio
Shared: Base Building · Strategy · Survival

Oxygen Not Included
Shared: Survival · Base Building · Strategy

Farthest Frontier
Shared: Strategy · City Builder · Building

IXION
Shared: Strategy · Survival · City Builder

Bee Island
Shared: Strategy · Tower Defense · City Builder

Against the Storm
Shared: Strategy · Base Building · City Builder

RimWorld
Shared: Strategy · Survival · Base Building

Infection Free Zone
Shared: Strategy · Base Building · Survival

Frostpunk 2
Shared: Strategy · Survival · City Builder

Kingdoms and Castles
Shared: Strategy · City Builder · Base Building

This War of Mine
Shared: Survival · Strategy · Atmospheric

Settlement Survival
Shared: Survival · City Builder · Strategy

Ostriv
Shared: Strategy · City Builder · Base Building

Banished
Shared: Strategy · City Builder · Survival

Becastled
Shared: Strategy · Base Building · City Builder

Endzone - A World Apart
Shared: Strategy · Survival · City Builder

Dwarf Fortress
Shared: Strategy · Base Building · City Builder