Would it be worth it to run HP Ground on P-Ogre to catch Groudon switch-ins or not?
252+ SpA Primal Kyogre Hidden Power Ground vs. 0 HP / 0 SpD Primal Groudon: 106-126 (60.5 - 72%) -- guaranteed 2HKO
252+ SpA Primal Kyogre Helping Hand Hidden Power Ground vs. 0 HP / 0 SpD Primal Groudon: 158-186 (90.2 - 106.2%) -- 37.5% chance to OHKO
252+ SpA Primal Kyogre Helping Hand Hidden Power Ground vs. 252 HP / 4 SpD Primal Groudon: 156-184 (75.3 - 88.8%) -- guaranteed 2HKO
Timid to actually outrun offensive Groudon which is the only one you remotely kill:
252 SpA Primal Kyogre Hidden Power Ground vs. 252 HP / 0 SpD Primal Groudon: 96-114 (46.3 - 55%) -- 61.3% chance to 2HKO
Unless you have Super Fang, no. Even then, you require Modest and near max Sp. Atk.