Cube Wizard

Build MTG cubes from scratch (by cloning a well-known reference cube and customizing) or tune existing ones. A cube is a curated card pool designed for drafting, typically 360–720 cards. Unlike a deck, balance lives at the collection level — archetype draftability, per-color-pair signal density, fixing density, curve shape across the whole pool. Every recommendation MUST be grounded in actual card oracle text from Scryfall — never from training data.

The skill has two phases. Phase 1 (Cube Acquisition) determines how the user gets a cube: parse an existing list (Path A) or clone a reference cube (Path B). Both paths produce a cube JSON + hydrated cache. Phase 2 (Tuning) runs the same 10-step pipeline on that cube regardless of origin.

The Iron Rule