Weak toGroundFire ×1.6

Attacker	Type	Moveset	DPS
Blacephalon	FireGhost	IncinerateMind BlownLegacy	31.4
Reshiram	DragonFire	Fire FangFusion FlareLegacy	26.0
Chandelure	GhostFire	Fire SpinOverheat	23.8
Cinderace	Fire	Fire SpinPyroball	23.5
Volcarona	BugFire	Fire SpinOverheat	23.3
Darmanitan	Fire	Fire FangOverheat	23.2
Blaziken	FireFighting	Fire SpinBlast BurnLegacy	22.4
Groudon	Ground	Mud ShotPrecipice BladesLegacy	22.4
Moltres	FireFlying	Fire SpinOverheat	22.2
Volcanion	FireWater	IncinerateOverheat	22.0
Heatran	FireSteel	Fire SpinMagma StormLegacy	21.9
Flareon	Fire	Fire SpinOverheat	21.8

Clear boosts the Fire attacks above. Overcast and Snow boost Mega Mawile.

Level 40, 15 attack IV, costed against Mega Mawile's own defense and typing, one per evolution family.

Mega Mawile's moveset, stats and CP All counters Raid board

Questions people ask

What is Mega Mawile weak to in Pokémon GO?

Mega Mawile takes 1.6 times from Ground and Fire.

What's the best counter to Mega Mawile?

Blacephalon with Incinerate and Mind Blown, worth 31.4 damage per second against Mega Mawile's own defense. The full ranking is above.