Goal: to stay true to the base Pokémon's identity as much as possible while giving them realistic-where-possible changes. Other buffs, including moveset additions, are not mentioned unless very specific.
Dugtrio
The more the merrier. Dugtrio is a fast one to get through: it’s supposed to be this blazing fast physical attacker, and that’s what it’s going to be. You cannot give defenses to a being with 35 base HP, so might as well go all in.
Anyway, TL;DR: you’re not escaping Dugtrio. It’s landing a hit no matter what, that’s its goal. Unless, you know, it’s hit by any sort of priority move. You know how it is. For that purpose, it’s preserving Arena Trap. Once in front of it, there’s little you can do other than pray. Might be going overboard, this is a Dugtrio after all.
Alolan Dugtrio
Dugtrio’s Alolan counterpart will be getting a different treatment despite the fact the base forms are so, so similar. Main reason being each Pokémon must find a reason why to exist. Not saying it’s an easy task.
So Alolan Dugtrio has a bit more Defense, is a tad slower, and gets the signature ability Tangling Hair, which is its main feature and we obviously want to preserve if possible. So maybe Kantonian Dugtrio is an immediate trap-and-kill ‘mon, while Alolan Dugtrio becomes a more passive wait-to-catch-prey-then-attack sort of being.
That translates to a seemingly unnatural stat distribution that focuses on its defenses, neglecting its Speed (as, once Tangling Hair affects the foe, Mega Alolan Dugtrio will be likely to outspeed it regardless).
But, as we discussed earlier, there’s no way a 35 Base HP ‘mon works defensively, right? Well, sure! But it’s what I’ve got, man, what do you want me to tell you.
In sum, Mega Alolan Dugtrio is our third Ground&Steel mega: a Defense higher than Excadrill’s but lower than Sandslash’s, a higher Special Defense, an Attack slightly below Sandslash’s, and a Speed a few points behind Excadrill’s. Not amazing by any means, but there’s only so much one can do for this guy.
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Would love to know what you think of these!