Weak toGroundElectricPsychic ×1.6

Attacker	Type	Moveset	DPS
Deoxys	Psychic	Charge BeamPsycho Boost	62.5
Regieleki	Electric	Lock OnThunder CageLegacy	55.2
Mewtwo	Psychic	ConfusionPsystrikeLegacy	50.1
Zeraora	Electric	Volt SwitchPlasma Fists	47.4
Zekrom	DragonElectric	Charge BeamFusion BoltLegacy	46.3
Xurkitree	Electric	Thunder ShockDischarge	45.7
Alakazam	Psychic	ConfusionPsychicLegacy	42.8
Groudon	Ground	Mud ShotPrecipice BladesLegacy	41.5
Azelf	Psychic	ConfusionFuturesight	41.5
Hoopa	PsychicGhost	ConfusionPsychic	41.3
Espeon	Psychic	ConfusionPsychic	41.3
Regigigas	Normal	Zen HeadbuttCrush GripLegacy	41.2

Rainy boosts the Electric attacks above. Overcast and Rainy boost Mareanie.

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

Mareanie's moveset, CP and shiny All counters Raid board

Questions people ask

What is Mareanie weak to in Pokémon GO?

Mareanie takes 1.6 times from Ground, Electric and Psychic.

What's the best counter to Mareanie?

Deoxys with Charge Beam and Psycho Boost, worth 62.5 damage per second against Mareanie's own defense. The full ranking is above.