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252 Atk Jirachi Fire Punch vs. 248 HP / 0 Def Scizor: 272-324 (79.3 - 94.4%)
252+ Atk Choice Band Scizor U-turn vs. 164 HP / 0 Def Jirachi: 188-222 (49.2 - 58.1%)
252 SpA Togekiss Heat Wave vs. 164 HP / 0 SpD Jirachi: 206-244 (53.9 - 63.8%)
Assuming rachi has attack and bulk at the same time.
I suggest Jirachi over Ferrothorn to deal with the threat u mentioned, which also has Rock and Wish for longevity.
And maybe u could try a LO set instead of CB on Hoopa so that it won't lock its move and still has enough damage output,
as well as gaining the ability to take out T-tar or some...