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Morpeko could make for a decent anti water team addition on Dark. Boosting its own speed with a decently strong STAB move thats also super effective without wasting your Dynamax slot is huge. Seed Bomb is also excellent against Seismitoad.
Putting its bulk aside, what heavily neuters Morpeko's...
A lot of the relevant Fairies from Gen 7 are gone, things are looking brighter for Hydreigon.
I've made it my designated Dynamaxer for OU and came up with this meme-ish set
Hydreigon @ Life Orb
Ability: Levitate
EVs: 4 Atk / 252 SpA / 252 Spe
Naive Nature
- Dark Pulse
- Draco Meteor...
Coming from someone who played Dark throughout Gen 7 I feel like giving some thoughts after trying out Gen 8.
-Knock Off becoming rarer didn't hurt Dark as much as I expected, since a good portion of its better Mons didn't rely on it as much or couldn't lear it anyway in the previous gen...