In the multiplayer map headlong, locate the banshee. Get in and fly to the large statue. Turn left, and go as high as you can. There is a close tunnel under your destination. Keep your high altitude and slowly aproach the roof without boosting. If you did it correctly, you are out of the map on a large gray area. Push the banshee down to the other player and have them do the same. Once you are both up, a little bit to your right you will find a tall building. Go to one of the corners and have one player stand on top of the other. This part is difficult. Have the player on top contiuously jump. The player on the bottom must sword cancel (B+X very quickly) while jumping. By doing this, you will slowly work your way up the side of the building. Once on top, there is a system of roofs and ledges, which will eventually lead to a long horizontal pole with an activation switch at the end. Hold X near the switch and go all the way back to the green portal near the turret and shotgun. Brace yourself, and walk in. You will be warped to the top of the skyscraper where a mustard-yellow warthog, the same as the one on the billboard, waits for your driving pleasure! ENJOY:-)!!!!!!!!!!!!!!!!!!!!!!!!!!!