A brutal yet cheeky medieval RTS where city-building, tower defense, and physics-driven slaughter collide in endless waves of besieging peasants, undead hordes, and invading armies.
Diplomacy is Not an Option is exactly what its title promises: a game where talking things out is off the table and the only negotiation tool you have is a trebuchet.
Door 407’s medieval RTS leans hard into wave-defense mayhem, gleeful dark humor, and gigantic battles that turn your idyllic countryside into a carpet of corpses and craters.
Concept & Setting
You play as a bored feudal lord in a crumbling kingdom where the king is incompetent, the economy is broken, and the peasants are (understandably) furious. Every “mission” is basically a new excuse for someone to rise up against you — rebels, neighboring lords, religious fanatics, even the undead.
Instead of a sweeping epic, the story is framed with tongue-in-cheek dialogue and absurd situations. The tone constantly swings between grim (famine, disease, mass graves) and comedy (your lord’s apathy, the king’s stupidity, and the sheer over-the-top scale of the violence). It never takes itself too seriously, but it does give just enough narrative context to glue each desperate siege together.
The world itself is a stylized medieval fantasy: villages, forests, farmlands, and fortified castles under constant threat. There are no diplomacy menus, alliances, or peaceful resolutions. If someone shows up on the map, they’re either working for you or they’re about to die.
Gameplay & Mechanics
At its core, Diplomacy is Not an Option is a hybrid of RTS army management, City-building and logistics, Tower-defense / horde-survival.
You start with a small keep, a handful of peasants, and a countdown to the first enemy wave. From there, the loop is simple on paper and wonderfully stressful in practice:
- Build and expand
Place houses, lumber camps, quarries, farms, warehouses, and defensive structures. The economy is straightforward but unforgiving; mismanage food or wood and your entire defense collapses.
- Raise an army
Peasants become archers, swordsmen, pikemen, siege crews, and more. You’ll constantly juggle workforce vs. military: do you draft builders into the army now, or let them finish the crucial walls first?
- Research and magic
A tech tree unlocks stronger units, better walls, siege engines, and magical “god powers.” You can call down meteors, heal troops, or — crucially — pause time with an active-pause spell to re-issue orders when the chaos gets overwhelming.
- Survive the waves
Enemy hordes attack on schedules and from different directions, escalating from ragged peasants to heavily armored knights, siege units, and supernatural threats. On higher difficulties, you’re playing a ruthless puzzle where every resource and wall segment must carry its weight.
The game offers multiple modes: a story campaign with escalating scenarios, Endless and Challenge modes for pure survival runs, a more relaxed Sandbox mode, and a map editor for custom setups. This gives the game a ton of replayability, whether you want carefully curated missions or improvised last stands.
Two things really set the gameplay apart:
- Scale – Late-game battles involve tens of thousands of units on screen. Arrows darken the sky, walls crumble, and the battlefield becomes a living maze of corpses and rubble.
- Simulation details – Corpses aren’t just visuals; they pile up, spread disease, and need to be buried in cemeteries or mass graves. Supply lines, food, and population growth matter. Neglect any of it and your city will implode even if your walls hold.
It’s difficult, demanding, and designed for players who enjoy “learning by losing.” Missions can last a couple of hours, and failing at wave 10 after meticulously building your fortress is both devastating and – if you’re the right kind of player – incredibly motivating.
Atmosphere & Style
Visually, Diplomacy is Not an Option goes for a clean, slightly cartoony low-poly look rather than gritty realism. Villages and soldiers are charmingly stylized, which makes the brutality of the battles oddly palatable. From a high zoomed-out view, you can admire your neat little town; zoom in and you get a chaotic mess of arrows, explosions, wizards, and screaming peasants.
The presentation shines most when the hordes arrive. Thousands of enemies crash into your defenses, physics sends bodies tumbling off walls and bridges, and the landscape gradually transforms into a tapestry of siege engines, craters, and shallow graves. It’s grim, but the exaggerated style and dark humor keep it from feeling oppressive.
The soundscape leans into that same mix: panicked battle shouts, siege engines creaking into place, catapults thudding, spells detonating, all carried by a suitably dramatic medieval-inspired soundtrack. It sells the fantasy of being a beleaguered lord orchestrating total chaos from the safety of your keep’s balcony.
Strengths & Who It’s For
Focused, addictive horde-defense loop
The game knows exactly what it wants to be: a wave-defense RTS. Everything — economy, tech, map design — is built around making each incoming siege more terrifying and more satisfying to survive.Huge, spectacular battles
Late-game defenses feel like playable cinematic set-pieces, with thousands of units clashing, walls breaking, last-second spell casts saving the day, and heroic retreats through kill-zones you carefully prepared hours earlier.High skill ceiling and rewarding mastery
Tactics and planning genuinely matter. Choke points, overlapping fields of fire, proper unit mix, and resource efficiency turn impossible waves into winnable ones. If you enjoy experimenting, optimizing, and “getting good,” this game will happily eat dozens of hours.Plenty of modes and replayability
Campaign, Endless, Challenge, Sandbox, plus a map editor and multiple difficulty levels mean there’s always another scenario to tackle or another fortress idea to test.Single-player RTS without competitive pressure
There’s no multiplayer ladder, no ELO, no rush meta. It’s you against the AI hordes, at your chosen difficulty, which makes it ideal for RTS fans who love the genre but don’t care about PvP.Strong overall reception
Critics generally rate it in the “good to great” range, and Steam user scores are very positive, especially praising the scale of the battles and the satisfying, challenging gameplay loop.
If you liked games like They Are Billions or the siege defenses of Stronghold and Age of Empires, Diplomacy is Not an Option hits that same “build a perfect murder-fortress, then pray” itch.
Verdict
Diplomacy is Not an Option is a love letter to the brutally unforgiving side of the RTS and tower-defense genres. It strips away diplomatic fluff and grand strategy layers to focus on one thing: the desperate joy of holding a doomed castle just a little longer than you thought possible.
It’s not trying to compete with the most complex city-builders or the most cinematic strategy games. Instead, it offers a tight, replayable loop of building, optimizing, and surviving ever-growing waves of enemies, backed by physics-heavy battles and darkly comic medieval misery.
If you want:
- A challenging single-player RTS with massive battles
- A focus on defense, planning, and “learn by losing”
- Enough modes and difficulty options to keep you experimenting for dozens of hours
…then Diplomacy is Not an Option is absolutely worth your time — and very likely, a lot of it.