Free · AGPL-3.0 open source
Riftbound tools built on a rules engine, not on a chatbot
A language model will read a Reaction card and tell you it can be played at the end of a Showdown, because that sentence reads fine. It is not a legal play. Everything here sits on top of code that owns the mechanical layer — and that is allowed to answer unsupported rather than invent something plausible.
What is here, and what is not
Stated exactly, because a tool that overstates itself on its own homepage has already failed the thing it claims to be good at.
- liveCard databaseEvery card with its full English rules text, searchable by name, text or region. No account, no install.
- buildingDeck builder and text importDecklists as plain text, so a deck moves between this and anything else you use. Legality checking is already written and needs an English surface.
- plannedRules assistantInteraction questions answered against the rules engine, with the clause each answer rests on — and an explicit refusal when the engine does not model the case.
- plannedDeck coachingHow a deck actually plays: keep rules, sequencing, what a matchup punishes. Gated on the engine finishing a game, which is honest work still to do.
Why the engine matters more than the model
Riftbound has a chain, it passes priority and focus, and the opponent can act during your turn — which is the property that decides how hard a card game is to model at all. The hard part was never that models are not clever enough. It is that somebody has to turn the rules into a program first, and the last serious public attempt at that got 4.8% of Magic cards exactly right while producing code that looked almost correct.
So the timing and permission kernel here runs under 21 executable conformance cases tied to official clauses, and the typed effect layer covers 12 operations and fails closed on anything else. It is AGPL-3.0 licensed and public, which means the scope and the limits can be checked instead of taken on trust.
Unofficial, and not endorsed by Riot Games
Card text comes from community-maintained databases and each card page credits its source. Card images are not served here — those belong to Riot, and this project has no licence for them. It is built for preparation and study; using it during a sanctioned event is against tournament rules.
Built by the team behind Riftbound Chronicle, a Traditional Chinese Riftbound site for players in Taiwan, where this work is used in production.