Hide in Plain Sight
The trait Improved Hide In Plain Sight in The Quiet Knife trait tree reduces the cooldown of this skill by up to 180 seconds and, at max rank, lets this skill cure all Poison, Disease, Fear and Wound effects that are present on you.
This is one of your major rescue skills. If the time arises when all hope is lost and your fellowship is failing, use HiPS to save yourself. It drops all threat and can save you lots of repair bills. The skill resets the cooldown on this skill, making it available more often.
It's also possible to get in stealth, so you can activate for a Fellowship Manoeuvre.
After using this skill, a creature will attack you after it comes out of being d. This can be used in your advantage; pull the creature you need to kill. it, use HiPS (all other creatures will reset), finish off.