add echo and sq and thats one hell load of energy being drained. get 2 of them and take out their entire energy supply and keep it down. You do of course start to run out yourself after a while.
The idea is to use Expertise to bring the cost down. 10 for 10 is a bad trade, but 10 for 4 isn't. This is one of those skills that's completely useless to any non-primary.
With 14 Expertise this is -10 energy + bow/prep damage to the enemy at the cost of 4 energy. Serpents Quickness and Quickening Zephyr can be used to shorten the recharge time a lot.
