Stormsurge should be an AP version of collector.

Stormsurge feels so toxic to play against because it just adds an extra 40-50% damage to burst champs. Even if they miss part of their combo, AP is still high enough that even just hitting 1 ability it tends to be enough to trigger Stormsurge. It already has the same bonus gold passive that collector has, just make it so that it executes under 5% HP, just like collector.