[Mivereous]

On the subject of this post, I think it would be pretty cool to round it all out and make it so that Acid Jet leaves a poison (does poison damage, inflicts poison at scaling %, or something) or acid line (reduce Armor DEF by scaling % while standing on it, take Acid damage while moving through it, other ideas).

[Autumn]

There's also the poison tiles that the snakes in the argentyle caverns have on "Slithering Earth", could be used as the tile for acid or just use them in general.

[Raigen.Convict]

While I agree on the tile effect for acid jet, let's NOT give the thing poison too, since on top of being one of the highest hp race of youkai, dragon, it also deals a damage type which is hard to resist, so having acid tiles and acid damage with the 2 def and res redux is fine with how strong it is.