How about mindgates? I can't tell what the opponent might bring.
Well, a deck with Aether Mark, Aether Pillar/Pends, Mindgates and Dims is considered a mono, right? No matter what your opponent brings, it is still a mono.
Moreover, a Deck with Steals can theoretically get any Pillar/Pend it wishes, but a monodark is still a monodark.
Finally, Mutation counts an an
card and Fallen Elf/Druid mutation count as
effect, no matter the element of the produced creature.
May the Brawlmasters correct me if I am wrong.