Sawyer using Intangibility.
Notable users:

Intangibility, also known as phasing, is the ability to alter one's molecular structure and any object they are in contact with to a state that can pass through physical matter; rendering the user immune to many forms of physical attack. Lieutenant Sawyer aka Ghost Soldier has this ability.


Someone in an intangible form have the properties of a gas such that extreme cold can slow him or her down. Superman used his cold breath to slow him down.