KeyForge is Richard Garfield's post-Magic-post-Netrunner game, and it is the card game that argued an entire generation of CCG players were wrong about deck-building: every KeyForge deck is unique, non-editable, and entirely the product of algorithmic generation.
The game
Designed by Richard Garfield and published by Fantasy Flight Games in 2018, KeyForge is a two-player duel where each player owns a pre-built deck. You cannot swap cards between decks, trade singles, or side-board. The entire chase is about the specific algorithmically-generated combination of cards in your deck. On each turn, you pick one House from the three your deck belongs to and only play cards from that House. Your goal is to forge three Keys by stockpiling Æmber.
The context
Garfield designed KeyForge explicitly as a philosophical counter to the Magic-style booster economy he invented. Every deck is a serialized, uniquely-named, uniquely-arted object. The naming algorithm ranges from the charming to the absurd ("Miss Rulf of the Obsolete Prophecy" is a real deck name). FFG published the first four sets before the license moved to Ghost Galaxy in 2022.
The collector angle
Call of the Archons, Age of Ascension, Worlds Collide, Mass Mutation and Dark Tidings are the FFG-era sets. Ghost Galaxy continued with Winds of Exchange, Grim Reminders, and Aember Skies. The most-sought decks are Archon-level rare House combinations with Evil Twin variants or low deck-numbers. Signed Richard Garfield decks from the 2018 launch event are the prestige items of the game.