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If Clauncher is under a succesful P/E move when you are to act, then use Tackle this action.
If Clauncher is to use Icy Wind this action, then use Thunderwave the first instance, Thunderbolt further instances.
Crabhammer - Water Pulse
IF Porygon is under the effects of a successful P/E move when you would act, use Swords Dance that action instead and push back, but not consecutively.
IF you have <18.1 HP when you would act, use Flail that action instead.