Single-player games like Diplomacy is Not an Option: Shareware
Below are 11 single-player Steam games similar to Diplomacy is Not an Option: Shareware, ranked by player overlap. Every pick carries Steam's Single-player category, so multiplayer-only titles or always-online games don't sneak in. imho.run pulls the category data from Steam directly — Single-player here matches what the store labels.
Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Diplomacy is Not an Option: Shareware page.
Ranked picks
- 1

Diplomacy is Not an Option
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy with Diplomacy is Not an Option: Shareware.
Diplomacy is Not an Option is a strategy game set in a medieval fantasy world. Build your town and defenses, raise huge armies and fight against massive hordes of enemies. How long can you survive?
- 2

Bergfried
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Build realistic medieval castles and defend them against rival knights. Bergfried is a strategy game featuring organic castle building and tactical siege battles. Manage your lands, plan your defenses and lead your troops to victory!
- 3

Towers & Goblins: The Last Stand
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Build towers, manage resources, and lead units to defend your kingdom against goblins. Every decision you make determines your kingdom's fate.
- 4

Here Comes The Swarm
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Here Comes the Swarm is a survival RTS with a pause button! Create your strategy, build, manage, and defend your settlements at your own pace. Take the fight to the hive mind and lead expeditions to deliver a deadly blow and eradicate your foes. Will you reclaim Ulora from the relentless Swarm?
- 5

Northgard: Definitive Edition
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Northgard: Definitive Edition is a critically acclaimed real-time strategy game based on Norse mythology. Lead your clan, uncover the secrets of a mysterious newfound continent and defeat your enemies to conquer the Throne!
- 6

Stronghold Crusader: Definitive Edition
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Gird your loins and sharpen your steel! Besiege 20 unique enemy lords and battle friends online, in this expanded remaster of the classic 'castle sim'. Relive history with new units, opponents, visuals, audio, campaigns, skirmish trails, co-op and larger maps.
- 7

Stronghold: Warlords
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Besiege Great Khans, Imperial warlords and Shōgun commanders in Stronghold: Warlords, the latest 'castle sim' from Firefly Studios. Command AI warlords across the battlefield as you build a castle economy and new gunpowder-fuelled siege engines!
- 8

Final Outpost: Definitive Edition
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Final Outpost is a survival strategy base-builder. You lead the last survivors of the apocalypse. Assign roles, craft tools, and manage resources carefully. Construct buildings, level up your citizens, and fortify your town against hordes of zombies. How many days can you survive?
- 9

URBO
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required.
URBO is a relaxing cozy city-building puzzle game where you create beautiful towns on floating islands. Begin with an empty grid of landscape, choose an architectural style and build. Watch the population grow and the city flourish.
- 10

Abra-Cooking-Dabra
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy and Simulation with Diplomacy is Not an Option: Shareware.
Abra-Cooking-Dabra is a cooking card game. Manage ingredients and make British dishes to keep toves, borogoves, and mome raths fed. Meet timers and fulfill puzzling orders despite the angry wacky Cat being your boss. You are Wonderland's new chef.
- 11

URBO: Dream One
Single-player alternative to Diplomacy is Not an Option: Shareware — playable solo, no multiplayer required. Shares Strategy with Diplomacy is Not an Option: Shareware.
URBO: Dream One is a meditative puzzle game where you build houses around the mysterious Tower. Let your mind wander through visions of an enchanted city on an island in the middle of the crystal clear waters of a vibrant lake.