Games like Fortified Swiss
Games like Fortified Swiss include DARK SOULS™: REMASTERED, Bloons TD 6, Orcs Must Die! 2, Monster Hunter: World, and Mount & Blade II: Bannerlord. We matched them by the tags players give Fortified Swiss on Steam (Action, Strategy, RPG, Tower Defense, and Difficult): closest matches first, and among equally close ones the better-known games.

DARK SOULS™: REMASTERED
Shared: RPG · Action · Difficult

Bloons TD 6
Shared: Strategy · Tower Defense · Great Soundtrack

Orcs Must Die! 2
Shared: Action · Tower Defense · Strategy

Monster Hunter: World
Shared: Action · RPG · Difficult

Mount & Blade II: Bannerlord
Shared: Strategy · RPG · Action

Sang-Froid - Tales of Werewolves
Shared: Strategy · Action · Tower Defense

ELDEN RING
Shared: RPG · Difficult · Action

Mount & Blade: Warband
Shared: RPG · Strategy · Action

Rock 'N' Roll Defense
Shared: Strategy · Action · Tower Defense

Bloons TD 5
Shared: Strategy · Tower Defense · Action

GemCraft - Chasing Shadows
Shared: Strategy · Tower Defense · Action

We Who Are About To Die
Shared: Action · Strategy · RPG

NieR:Automata™
Shared: RPG · Action · Great Soundtrack

Command & Conquer Red Alert™ 2 and Yuri’s Revenge™
Shared: Strategy · Action · RPG

Orcs Must Die!
Shared: Action · Strategy · Tower Defense

DARK SOULS™ III
Shared: RPG · Difficult · Great Soundtrack

Plants vs. Zombies GOTY Edition
Shared: Strategy · Tower Defense · Great Soundtrack

Ori and the Will of the Wisps
Shared: Action · Beautiful · Great Soundtrack

Total War: WARHAMMER
Shared: Strategy · RPG · Strategy RPG

Kingdom Rush Vengeance - Tower Defense
Shared: Strategy · Tower Defense · Difficult

Kingdom Rush Origins - Tower Defense
Shared: Strategy · Tower Defense · Difficult

Deathtrap
Shared: Action · RPG · Tower Defense

Kingdom Rush - Tower Defense
Shared: Strategy · Tower Defense · Action

DARK SOULS™ II: Scholar of the First Sin
Shared: RPG · Action · Difficult