Rule 708.6c

If anything performs a comparison involving multiple characteristics or values of one or more split cards in any zone other than the stack or involving multiple characteristics or values of one or more fused split spells, each characteristic or value is compared separately. If each of the individual comparisons would return a "yes" answer, the whole comparison returns a "yes" answer. The individual comparisons may involve different halves of the same split card. Example: Sunforger has an ability that reads, "{R}{W},Unattach Sunforger: Search your library for a red or white instant card with converted mana cost 4 or less and cast that card without paying its mana cost. Then shuffle your library." This ability can be used to cast either half of Research/Development, as Research has converted mana cost 2 (even though Development has converted mana cost 5) and Development is red (even though Research is neither red nor white).

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