Games like Brigand: Nightmare
Games like Brigand: Nightmare include Fallout 4, Fallout: New Vegas, S.T.A.L.K.E.R.: Shadow of Chornobyl - Enhanced Edition, BioShock Infinite, and Tainted Grail: The Fall of Avalon. We matched them by the tags players give Brigand: Nightmare on Steam (Adventure, RPG, Indie, Strategy, and Action): closest matches first, and among equally close ones the better-known games.

Fallout 4
Shared: RPG · Adventure · Post-apocalyptic

Fallout: New Vegas
Shared: RPG · Post-apocalyptic · Adventure

S.T.A.L.K.E.R.: Shadow of Chornobyl - Enhanced Edition
Shared: Adventure · RPG · Action

BioShock Infinite
Shared: Action · Shooter · RPG

Tainted Grail: The Fall of Avalon
Shared: RPG · Adventure · First-Person

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

S.T.A.L.K.E.R.: Call of Prypiat - Enhanced Edition
Shared: Adventure · RPG · Action

S.T.A.L.K.E.R. 2: Heart of Chornobyl - Standard Edition
Shared: Post-apocalyptic · RPG · Shooter

PUBG: BATTLEGROUNDS
Shared: Shooter · Action · Adventure

Freeman: Guerrilla Warfare
Shared: Strategy · RPG · Action

Monster Hunter: World
Shared: RPG · Action · Adventure

Remnant: From the Ashes
Shared: RPG · Adventure · Action

S.T.A.L.K.E.R.: Clear Sky - Enhanced Edition
Shared: Adventure · RPG · Action

Fallout 3
Shared: RPG · Post-apocalyptic · Adventure

Kenshi
Shared: RPG · Post-apocalyptic · Immersive Sim

Sands of Salzaar
Shared: RPG · Strategy · Adventure

Counter-Strike 2
Shared: Shooter · Action · Strategy

Borderlands 2
Shared: Action · Shooter · RPG

Wolcen: Lords of Mayhem
Shared: RPG · Adventure · Action

Warhammer 40,000: Rogue Trader
Shared: RPG · Strategy · Adventure

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

Far Cry® New Dawn
Shared: Action · Adventure · Post-apocalyptic

Rust
Shared: Adventure · RPG · Action

Dead Age
Shared: RPG · Strategy · Adventure