#0801 · Gen 7 · Mythical

Magearna — Best counters

Weaknesses

	Pokémon	Fast move	Charged move	Weather	Score
1	Blaziken (Mega)	fireFire Spin	fireBlast BurnELITE	Clear	10013.2
2	Charizard (Mega Y)	fireFire Spin	fireBlast BurnELITE	Clear	9712.8
3	Groudon (Primal)	groundMud Shot	groundPrecipice BladesELITE	Clear	9712.7
4	Blacephalon	fireIncinerate	fireOverheat	Clear	8911.7
5	Garchomp (Mega)	groundMud Shot	groundEarthquake	Clear	8611.3
6	Reshiram	fireFire Fang	fireFusion FlareELITE	Clear	8511.2
7	Landorus (Therian)	groundMud Shot	groundSandsear StormELITE	Clear	8411.0
8	Charizard (Mega X)	fireFire Spin	fireBlast BurnELITE	Clear	8310.9
9	Chandelure	fireFire Spin	fireOverheat	Clear	7810.3
10	Houndoom (Mega)	fireFire Fang	fireFire Blast	Clear	7810.3
11	Volcarona	fireFire Spin	fireOverheat	Clear	7610.0
12	Darmanitan (Standard)	fireFire Fang	fireOverheat	Clear	7610.0
13	Groudon	groundMud Shot	groundPrecipice BladesELITE	Clear	749.7
14	Ho Oh	fireIncinerate	fireSacred FireELITE	Clear	739.6
15	Blaziken	fireFire Spin	fireBlast BurnELITE	Clear	739.6
16	Moltres	fireFire Spin	fireOverheat	Clear	729.5
17	Camerupt (Mega)	fireIncinerate	fireOverheat	Clear	729.4
18	Swampert (Mega)	groundMud Shot	groundEarthquake	Clear	729.4
19	Heatran	fireFire Spin	fireMagma StormELITE	Clear	729.4
20	Volcanion	fireIncinerate	fireOverheat	Clear	719.4

Magearna is weak to Ground (×1.6), Fire (×1.6).
Watch its Water/Normal moves — counters like Blaziken (Mega) and Charizard (Mega Y) take super-effective damage from them.
Clear weather boosts Fire moves ×1.2 — the best time to battle Magearna.

Rankings are estimated cycle DPS (attack stat × move damage ÷ cycle time, with STAB and type effectiveness). Not a full battle simulation.