Toxapex @
Payapa Berry
Ability: Regenerator
EVs: 252 HP / 92 Def / 164 SpD
Calm Nature
IVs: 0 Atk
-
Toxic
- Scald
- Haze
- Recover
Payapa Berry can lure Mega Alakazam, specially because Trace can copy the always obnoxious Regenerator. Mega Alakazam uses Psychic and Payapa Berry will reduce the damage, just the enough to let it to use Toxic and put a timer to Mega Alakazam, which will be a problem even with Recover.
252+ SpA
Alakazam-Mega Psychic vs. 252 HP / 164+ SpD Payapa Berry Toxapex: 120-142 (39.4 - 46.7%) -- guaranteed 3HKO
This sets have some other uses, like putting a timer to Mega Medicham, Tapu Lele (barely surviving things like Z-Psychic if it's at full health) and Psychium Z Volcarona, in the last case it can also take advantage of the improved matchup to use Haze and remove Volcarona's boosts
252 Atk
Pure Power Medicham-Mega Zen Headbutt vs. 252 HP / 92 Def Payapa Berry Toxapex: 142-168 (46.7 - 55.2%) -- 69.1% chance to 2HKO
252 SpA
Tapu Lele Shattered Psyche (160 BP) (Psyshock) vs. 252 HP / 164+ SpD Payapa Berry Toxapex in Psychic Terrain: 234-276 (76.9 - 90.7%) -- guaranteed 2HKO
252 SpA
Tapu Lele Shattered Psyche (175 BP) (Psychic) vs. 252 HP / 164+ SpD Payapa Berry Toxapex in Psychic Terrain: 255-301 (83.8 - 99%) -- guaranteed 2HKO
+1 252 SpA
Volcarona Shattered Psyche (175 BP) vs. 252 HP / 164+ SpD Payapa Berry Toxapex: 175-206 (57.5 - 67.7%) -- guaranteed 2HKO