Hope was quite shocked by what Emily just did. She'd imaged Emily would throw out another exploding attack or something like that. But not wasting the window she was given, she quickly released the spell she was preparing as the hole Emily had created was already closing.
"Descent of the poison cloud!" Hope exclaimed as a dark green cloud that suddenly appeared in the sky above the spider descended and enveloped it whole.
Most of the poison was stopped by the dome but some of it got through the two holes created by Emily's attack, one in the front and another in the back. Even so, the little that got through was quite effective as it had the spider's newly acquired wound to exploit. The spider started feeling dizzy and couldn't effectively attack as before. But that's all the poison managed to do since there wasn't a lot that got through the holes on the dome before they closed off.