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I agree that you disagree with the above quite a bit particularly on the issue of Zygarde, I also think the mon is quite a bit overrated and I want to agree with your reasons why. Just to assert your comparison point: while don is another mon you are known for liking, I too concur that it should be ranked higher than Zyg and I'll give some of my reasons why below:
Hey, nice post :') I just wanna say that I'm unsure if Quag will still viable, because Photon Geyser will ignore Unaware, so it can't check SD Photon Necro. (tho it should wall Photon-less NDM with Scald burn but idk if it is a thing)