#0483 · Gen 4 · Legendary

Dialga — Best counters

Weaknesses

	Pokémon	Fast move	Charged move	Weather	Score
1	Lucario (Mega)	fightingForce PalmELITE	fightingAura Sphere	Overcast	10013.9
2	Groudon (Primal)	groundMud Shot	groundPrecipice BladesELITE	Clear	9212.7
3	Blaziken (Mega)	fightingCounter	fightingFocus Blast	Overcast	8712.1
4	Heracross (Mega)	fightingCounter	fightingClose Combat	Overcast	8311.5
5	Garchomp (Mega)	groundMud Shot	groundEarthquake	Clear	8111.3
6	Alakazam (Mega)	fightingCounterELITE	fightingFocus Blast	Overcast	8111.2
7	Landorus (Therian)	groundMud Shot	groundSandsear StormELITE	Clear	7911.0
8	Pheromosa	fightingLow Kick	fightingFocus Blast	Overcast	7810.8
9	Lucario	fightingForce PalmELITE	fightingAura Sphere	Overcast	7610.6
10	Lopunny (Mega)	fightingDouble Kick	fightingFocus Blast	Overcast	7510.4
11	Gallade (Mega)	fightingLow Kick	fightingClose Combat	Overcast	7410.3
12	Latios (Mega)	dragonDragon Breath	fightingAura Sphere	Overcast · partial	7210.0
13	Terrakion	fightingDouble Kick	fightingSacred SwordELITE	Overcast	7210.0
14	Groudon	groundMud Shot	groundPrecipice BladesELITE	Clear	709.7
15	Gengar (Mega)	ghostLickELITE	fightingFocus Blast	Overcast · partial	689.5
16	Keldeo (Ordinary)	fightingLow Kick	fightingSacred Sword	Overcast	689.4
17	Keldeo (Resolute)	fightingLow Kick	fightingSacred Sword	Overcast	689.4
18	Swampert (Mega)	groundMud Shot	groundEarthquake	Clear	689.4
19	Urshifu (Single Strike)	fightingCounter	fightingDynamic Punch	Overcast	679.4
20	Urshifu (Rapid Strike)	fightingCounter	fightingDynamic Punch	Overcast	679.4

Dialga is weak to Fighting (×1.6), Ground (×1.6).
Watch its Dragon/Steel/Electric moves — counters like Garchomp (Mega) and Latios (Mega) take super-effective damage from them.
Overcast weather boosts Fighting moves ×1.2 — the best time to battle Dialga.

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