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Guide to Battle Tree (Singles)
Using mons in the Alola Dex
Note that there are almost no actual Alola Mons worth using. Toxapex is okay but you're going to be stalling forever, which is counter intuitive. This is NOT comprehensive, just some things me and friends have been successful with.
Good mons to use:
>Fast Physical Attackers
Garchomp
Mega Mence
Mega Luke
Mega Gyara
Pheremosa
Kartana
>Fast Special Attackers
Mega Luke
Nihilego
Tapu Lele
Gengar
>Bulky Attackers
Aegislash
M-Sableye
Scizor/M-Scizor
Dragonite
>Utility Mons
A-Persian (Parting Shot)
Celesteela
A-Ninetales (Aurora Veil)
Omitted Megagross and M-Zam because they rely on less-than-accurate coverage moves. Same can be said of all/most similar mons that need to use coverage moves like that. Mega Luke is fine because it gets Adaptability Aura Sphere.
Pokemon with Memento and shit aren't as great this Gen because the AI seems to switch out more often. They don't switch out terribly often, but more often than in past games. Idk what the AI's criteria for switching is. I taunted Red's Venu and it Struggled itself to death. Meanwhile, I had an AI recall her Throh because it couldn't do anything to my Aegislash.
Generally if a mon has under 100 base speed it's too slow to use successfully unless it has lots of bulk to offset the crits and shit you're gonna be dealing with.