This was posted on the Neverwinter forums a while ago... They're planning on patching it in a future update (but who knows when?) so take advantage of it NOW while you can!!!
EDIT::: PATCHED!
Think this got patched!
Patch Notes: NW.3.20130723a.2 July 31, 2013 at 5:16pm
Frozen Power Transfer Feat: Fixed an issue where this could extend the duration of all other effects on the Control Wizard.
/EDIT
CW exploit how to one shot bosses.
Spec into thaumaturge tree making sure to get Frozen Power Transfer. This allows you when auto attacking with chilling cloud to build hiding stacks that increase the damage of non Dot Aoe damage spells (Chill strike in tab, Steal time, Shield, icestorm.). You have about a 8-10 second time to auto attack before your stacks fall off. Within just a few minutes of auto attacking the training dummies I was up to 1million damage with chill strike. All you have to do in dungeons is just keep chain pulling to keep building up stacks.
EDIT: This does not work without Evocation Rank 3. Just tested.
One Shotting the last boss in CN. Please fix this!
http://www.youtube.com/watch?v=kE7qE...lGVC4o6THBLIFQ
8:50 - 1 million crit
These are the feats I run to make this happen.