Valve did more than just have Left 4 Dead 2‘s new "Dark Carnival" campaign on display to be played by attendees at the Penny-Arcade Expo. They announced a new zombie boss for the game and details on some exclusive pre-order weapons.
The newly unveiled boss zombie is the Jockey, which is designed to attack lone survivors and wrestle control of their movement away from them into fires, off ledges, or straight into the middle of a zombie horde. The Jockey joins the Charger and Spitter, announced at E3 and Comic-Con respectively, as new boss infected for the sequel.
Valve also announced that some of the 20 new items for Left 4 Dead 2 will be offered as a "pre-sell exclusive with select retailers" and named the "electric guitar, machete, and the American baseball bat" as examples.