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The first ability that came to mind was weirdly enough Rain Dish only because usually when I think of imagery of waves or of a tsunami in media they are accompanied by a rain storm, and since drizzle is banned this is the closet I can get to it.
I think Water Compaction will be a nice flavor ability but I will also suggest Aroma Veil to be considered in its sense of water cleaning and considering its fairy typing
I'd like to throw in Wonder Skin -- I think it thematically fits nicely with Rough Skin and Multiscale being skin based abilities / also contrasts rough skin and brings out the 'gentle giant' flavor~
Okay so I am a tad later than I wanted to be with this (I wanted it up Wednesday but work and life have been kicking my ass recently lol) but here is the flavor ability slate:
Water Veil
Pressure
Damp
Hydration
No Ability
Keeping it short and sweet, these are the abilities I felt got the most support while also maintaining flavor as we don't want anything to have competitive implications that can mess with Cres doing what it does already. Let's get ready to see what ausma has to say and hopefully move onto voting soon!