This plane is used for attack missions. It's outfitted with brand new technology, seen in the orange dots on the underbody. The plane is fast, quick, and undetectable (the orange dots seem to be a source of this, strangely). The two main exhaust barrels give it a distinctive look.
It's primarily used for specialized missions in which the Raptor has a specific, known target. That's what the large single missile is for.
By the way, that main cockpit piece came in a McDonald's set, according to the inscription on the plastic underneath the piece. I found it at my Grandmother's house. How the piece got there, I have no idea. It must have been a racecar/Lego promo.