Weak toGroundFire ×1.6

Attacker	Type	Moveset	DPS
Blacephalon	FireGhost	IncinerateMind BlownLegacy	29.0
Reshiram	DragonFire	Fire FangFusion FlareLegacy	24.1
Chandelure	GhostFire	Fire SpinOverheat	22.0
Cinderace	Fire	Fire SpinPyroball	21.7
Volcarona	BugFire	Fire SpinOverheat	21.5
Darmanitan	Fire	Fire FangOverheat	21.4
Blaziken	FireFighting	Fire SpinBlast BurnLegacy	20.7
Groudon	Ground	Mud ShotPrecipice BladesLegacy	20.7
Moltres	FireFlying	Fire SpinOverheat	20.5
Volcanion	FireWater	IncinerateOverheat	20.3
Heatran	FireSteel	Fire SpinMagma StormLegacy	20.2
Flareon	Fire	Fire SpinOverheat	20.1

Clear boosts the Fire attacks above. Overcast and Snow boost Zacian.

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

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

Questions people ask

What is Zacian weak to in Pokémon GO?

Zacian takes 1.6 times from Ground and Fire.

What's the best counter to Zacian?

Blacephalon with Incinerate and Mind Blown, worth 29.0 damage per second against Zacian's own defense. The full ranking is above.