Phasing is the ability to pass through solid matter.
- D.L. Hawkins was the first to demonstrate this ability.
- Samir Mellouk has this ability.
- Peter Petrelli has absorbed this ability. He lost it when his father stole it from him.
- A skinny guy has also demonstrated this ability.
- In a possible future, Sylar has stolen this ability.
- According to NBC.com's interactive map, Felipe Acerra has this ability.
D.L. can use this ability selectively, passing all or part of his body through a solid object. He can reach through a solid barrier and manipulate something on the other side (like a door handle, for example).
When D.L. phases through something, the surface of the object distorts, as if liquefied. The part of D.L.'s body and the rest of the object is not being phased remain solid.
Phasing changes D.L.'s body, but it is unclear as to whether it also changes the object he is passing through.
D.L. can use this power to put his hand into another human being. This can be harmful to the other person. It is unknown whether the interaction itself is harmful or if D.L. does something inside the other's body. Phasing through Jessica's chest incapacitated her, while phasing through Linderman's head killed him instantly.
D.L. can phase other material besides himself. For example, his clothes stay with him when he passes through walls and other materials. He has demonstrated the ability to phase at least one other person when moving through solid materials. He has implied that he could use his power to leave another person merged with a wall or other object.
D.L. used his ability to walk himself and someone else he is carrying through fire, without getting burned. He also uses his power to allow a person's punch to pass through his body. He also used his power to fall through the floor of several stories into a basement.
Sylar was able to use the ability selectively and effectively; he phased through a door, grabbed Peter, and phased him through the door, pulling him to the other side.
Daphne Millbrook used Samir's ability to steal the Mona Lisa; as she held Samir's hand, she and Samir were both able to phase the painting out of its case and leave a fake in its place. Samir also used the power to escape from Sabine and Julien by phasing and sinking a level down into the sewers. However, when various clones of Julien Dumont appeared and surprised him, he lost his focus and became tangible again, allowing Julien to hit him.
Peter has demonstrated this ability twice. He walked through a wall of his cell at Primatech Research, and then walked through at least one more, taking Adam with him. Peter also used this ability somewhat unintentionally (due to his memory loss) when he was straining against ropes that bound him to a chair. He was surprised when his hands passed through the ropes, freeing him.
The skinny guy demonstrated his ability by phasing a kick from Rachel Mills through his chest.