White, fortified with extra minerals!
SPECIAL RULE: After the draft, the only Basic Lands you can add to your deck are plains.
Every card in the cube can be cast off of either Plain, life loss, or a colorless source.
Activated abilities of other colours exist, but you will need to draft the appropriate fixing to access those.
Archetypes:
Artifacts
Soul Sisters - Lifegain
Flicker
Aggro
Tap Out Control
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