If the calling actor does not have a Missile state, then 99% chance of doing nothing.
If the calling actor has a Missile state, then 88% chance of doing nothing followed by a 16% chance of jumping to the Melee state. If both chances fail, then there is a separate 50% chance of jumping to the Melee state if the target is out of melee range.
In either case, should all conditions fail and the target is out of melee range, it will jump to the Hump state and then play the sound "SerpentActive" on the Body channel.
This codepointer is restricted to Serpent and derived classes.