Body Snatch is a mental ability introduced in Destroy All Humans! 2.
This ability allows Crypto to take over the body of another person (replacing the Holobob from the first game). Once in a body, Crypto's energy bar will be replaced with that of the current host, which steadily decreases the longer he stays inside of the victim.
When it reaches zero, Crypto is expelled and the host is killed. If Crypto expels himself early, the person will still be alive (albeit, with less health), but if it is a hostile, it will attack Crypto.