Took a group of:
Level 14's: Enchanter, Shaman, Druid, Warrior, Cleric
Level 15: Necromancer
all untwinked.
The group was able to handle single sporlings with no trouble. Two sporling pulls were a bit more exciting but manageable. The Netherbian drones were manageable on single or double pulls if the druid and/or necro could get snare/darkness to land to prevent the dying mob fleeing and bringing friends. About a blue bubble of xp per character per kill.