Its not hold, it's immob. It's mainly useful for the damage, which is pretty nice, and it's the only purely negative energy attack in the set.
ok kl, cheers, and i meant immob not hold 
bad phrasing
i find it useful to oneshot minions that are fleeing, it actually has quite a good range on it
@ExtraGonk
Lo, i realise people have probably asked this but i just wanted to try and find out. What is midnight grasp for? the damage is not amazing and personally i don't find the hold overly useful since your already right up next to them.
I'm obviously missing a lot of obvious things here and if you could point them out it would be nice so i can make use of the power.
Cheers in advance