KeyForge Master Rulebook Updated to v17.1

Published On: September 11, 2023

The KeyForge Master Rulebook (MRB) is the comprehensive rules of play for the game of KeyForge. It is the game’s most authoritative source and contains a detailed glossary, official errata, frequently asked questions, and a timing chart. It is primarily a reference document to help players find answers to specific questions. We update this rulebook periodically as new cards sets are released and as new questions arise about how to resolve various card interactions that occur during games.

Note that if you’re new to KeyForge, the best ways to learn how to play the game are to read Learn to Play KeyForge and to watch our video tutorial.

What’s New in Version 17.1?

This is a housekeeping update to the MRB focused on clarifying several cards from Winds of Exchange. It includes a few updated glossary definitions, several new FAQ entries, and errata for two new cards. Let’s take a closer look at these changes.

Updated Glossary

Five glossary terms received small updates for better clarification: Chain Bidding and Chain Handicap (both optional rules for casual play), Fight, Omega, and Playing Cards.

Of these, the update to Playing Cards is probably the most important one to call out: When you play an upgrade on an opponent’s creature, you still control the upgrade even if the creature to which it is attached remains under the control of your opponent. Note this is not a change to the rules; this is how upgrades have always worked, but it is a rule that can be easy to overlook.

Questions, Questions, So Many Questions

There are new FAQ entries for Gĕzdrutyŏ the Arcane, Rampaging Brutodon, Researcher, and The Promised Blade (all of which are new cards from Winds of Exchange).

Gĕzdrutyŏ the Arcane is a tricky cyborg with an ability that seems simple at first glance: it steals 2 Æmber then transforms into a token creature by flipping itself facedown. (“I’m definitely not the thief you’re looking for.”) But in some situations, it can be hard to know how to resolve this ability correctly, especially if your opponent takes control of Gĕzdrutyŏ the Arcane. We’ve addressed several of these situations in the FAQ.

Both Rampaging Brutodon and Researcher have abilities that are usually very straight forward. But in some cases, it’s not obvious, especially for newer players. We’ve clarified these in the FAQ.

The Promised Blade has caused a lot of arguments (always friendly, we’re sure) about what happens when both players control the same number of creatures. The simple answer is the active player decides what happens. This may seem counter-intuitive to some players (if both players have the same number, how can one player have the fewest?), but it is in keeping with how we resolve ties for “most powerful” or “least powerful” creatures.

Two existing FAQ entries have also been updated for the sake of greater clarity: Endless Hordes is in fact limited by the rule of six, and the old Ghosthawk + Sinder combo cannot create a situation where Ghosthawk has three neighbors during the resolution of its ability.


We don’t like to issue errata for existing cards because we know how frustrating it can be to have another player tell you “it doesn’t work like that anymore.” Card errata is never something we do lightly, but there are two cards from Winds of Exchange that need it: Corner the Market and Curse of Forgetfulness.

The original wording on Corner the Market improperly described it as a replacement effect, which had the result of making it impossible for the person who played the card to verify their opponent was resolving the effect properly. Corner the Market should read:

Play: During your opponent’s next turn, they cannot play cards, and each time they discard a card from their hand, they may archive that card from their discard pile.

Curse of Forgetfulness has been mistakenly printed in two different versions. The errata clarifies which version is the correct version that all instances of that card should use:

Treachery. (This card enters play under your opponent’s control.)

At the end of your turn, purge the top card in your discard pile.

Download the latest version of the KeyForge Master Rulebook and forge some keys!

Return to Recent News