Mutant Mobility [HEHO Content]

Due to your extensive experimentation with various mutagens and tinkering with infusing your body and blood with magic, an interesting result of this is that you have become somewhat unstable from a matter perspective. The benefit of this is that you are able to instantly teleport across a room or battlefield, giving no time for others to react to your traversal. Unfortunately, the downside is that your phasing is imperfect and you are hurt whenever you do so.

On your turn, as a free action when you use your movement, you can choose to expend hitpoints in order to turn that movement into a Blink.

A Blink consumes hitpoints equal to the number of feet moved divided by 5 (or 1hp per square).
When you Blink away, no opportunity attacks can be made against you.
When you blink from a concealed position into melee range of an enemy and strike, you count as an unseen attacker and get advantage on your attack.

This ability should never ever under any circumstances be used in the water, as water makes it extremely difficult for your matter to come back together.
Using this ability in water makes you take 10hp per square moved and you do not count as an unseen attacker as you are slow to react afterward.