The tainted flesh of a corrupted doppelganger left a permanent mark on you and changed your body. The dark purple lines on your skin can be hidden with the Changeling's Shapechanger ability. Your flesh is now stretchy, and your joints are unrestricted by normal anatomy, unnaturally bending in any direction. 

You now have the following traits.

Stretchy limbs:
You can interact with objects 10 feet away. Your reach with Melee Weapons is increased to 10ft.

Tentacle Growth:
As a bonus action, you can extrude a tentacle from any part of your body. It is up to 6 inches wide and 10 feet long, It says extended until you use as bonus action to reabsorb it into your body. As part of the same bonus action and as a free action until reabsorb, you can use this tentacle interact with an object, open or close a door or container, or pick up or set down a Tiny object. The tentacle can’t attack, activate magic items, or lift more than 10 pounds.

Contortionist:
You have advantage on ability checks or saves to escape grapples or restraints.