>>54784812It’s a doubles fight. IIRC you have a Magcargo and Cacturne. You have Magcargo use Rock Slide to kill the first two Shedinja and have Cacturne (who outspeeds Magcargo) use Spikes to kill the incoming Shedinja. A Pokemon is sent out immediately after dying in Gen 3 doubles so if Rock Slide hits both, the entire team will die on turn 1.
