Deadpool, Vol. 3 #2 (2008)

Secret Invasion - One of Us, Part 2: One of Them
Deadpool has joined ranks with the Skrulls, offering his own DNA to better equip their super-skrulls. Of course, having his healing factor is only half the battle. You also need his skill, his speed, his humor, and his complete and utter insanity.
Release Date: 2008