The Castle Doctrine — cheap CD keys, compare prices
Is it worth buying?
Reviews are mixed (Metacritic 58 · Steam 49%) · The price is well above its low (was €1.64) — worth waiting for a drop or setting an alert Notify me on a drop
About the game
The Castle Doctrine is an indie strategy game built around defense and burglary. You turn your own house into a deadly maze of traps to protect your family and valuables, while attempting to rob other players' equally dangerous homes. Its harsh, unforgiving design, where a single mistake can be permanent, drives the tension. A stark black-and-white minimalist style underlines the paranoia and tactical mind games between players.
Did you know?
The Castle Doctrine was created by independent designer Jason Rohrer, known for his experimental games.
Best price today
€3.29
· · check “Region” on the seller’s page
Steam · Official store · Steam
Global key · check “Region” on the seller’s page
You pay Steam directly · same price as on their site
Notify me when it drops below €2.96
- On Steam
- €3.29
- all-time low
- €1.6427 Jun
- Average low, 5 mo.
- €2.30
The cheapest The Castle Doctrine key right now costs €3.29 at Steam. (Prices as of )
Offers 1 · PC · from €3.29
Prices as of
No offers match these filters — try widening them.
Listed seller price shown — payment fees may vary by method.
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Lowest official since we started tracking (Jul 2026)
€1.64
Oct 2026
Monthly price lows
| Month | Lowest official | Lowest keyshop |
|---|---|---|
| Oct 2026 | €1.64 | — |
| Sept 2026 | €3.29 | — |
| Aug 2026 | €3.29 | — |
| Jul 2026 | €1.64 | — |
| Jun 2026 | €1.64 | — |
Lowest in-stock price per month from our price history; the current month is the low so far.
How to activate your key
- Steam key — open the Steam client → Games → Activate a Product on Steam → enter the key. Stores with this activation: Steam
System requirements
| Minimum | |
|---|---|
| OS | XP or later |
| Processor | 900 MHz |
| Memory | 40 MB RAM |
| Graphics | Onboard Graphics |
| Storage | 10 MB available space |
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About this game — FAQ
Does The Castle Doctrine have multiplayer?
Yes, The Castle Doctrine has multiplayer.
Does The Castle Doctrine support crossplay?
Yes, The Castle Doctrine supports cross-platform multiplayer.
What languages does The Castle Doctrine support?
The Castle Doctrine is available in: English.
Does The Castle Doctrine use Steam Cloud saves?
Yes, The Castle Doctrine uses Steam Cloud, so your saves sync across devices.
FAQ
Where is the cheapest place to buy a The Castle Doctrine key?
The cheapest The Castle Doctrine key is currently sold by Steam for €3.29. The lowest price we have ever recorded for this game: €1.64.
How much does The Castle Doctrine cost?
The Castle Doctrine currently costs from €3.29 — the cheapest offer across the stores we track.
Is Steam an official store or a keyshop?
Steam is an official store — keys come directly from the publisher or an authorized distributor.
Are keys from these stores legal?
Buying is legal — keys come from the grey market, so a small deactivation risk exists. So before paying, check the seller's buyer protection.
Which key region should I pick?
Global activates everywhere. Regional keys (Europe, North America, RU-CIS) only work on accounts from that region — use the Region filter to match your account.
What is an activation platform?
The service where the key activates — Steam, GOG, Epic or the publisher's platform. A key for one platform won't work on another, hence the separate filter.
What's the difference between editions?
Standard is the base game; Deluxe usually adds an expansion or bonus content. The edition filter shows exactly that variant, with no mixed prices.