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+6 252+ SpA Metronome Flash Fire Mewtwo-Mega-Y Helping Hand Battery boosted Stored Power (620 BP) vs. -6 0 HP / 0- SpD Fluffy Shedinja in Sun on a critical hit: 299263216 - 352074400 (29926321600 - 35207440000%)
Courtesy of Wrath of Alakazam for the calc.
+6 252+ SpA Metronome Flash Fire Mewtwo-Mega-Y Helping Hand Battery boosted Stored Power (620 BP) vs. -6 0 HP / 0- SpD Fluffy Shedinja in Sun on a critical hit: 299263216 - 352074400 (29926321600 - 35207440000%)
Courtesy of Wrath of Alakazam for the calc.