Quote from Lithl »In Shadowmoor/Eventide, the filter duals were largely responsible for people playing triple and quadruple color requirement cards in multiple colors without worry, like holding up mana for Cryptic and then flashing Cloudthresher when the Cryptic wasn't needed. Chaining filters together can even get you to heavy mana cost requirements in three or more colors.
Exactly! Which, also, is an incredibly greedy line of play and why Blood Moon would have been a perfectly reasonable reprint in that block (though I'd argue it wasn't so much the filters that made this deck possible, but the existence of Reflecting Pool + Vivids).
That kind of fixing is powerful, grossly powerful. But hey if they're gonna give it out...I'm gonna take it haha. Let me keep Grand Abolisher-ing into Necropotence into Kiki-Jiki