Warning: Spoilers! As we did when the Mythic Map Pack was released, Joystiq brings you a quick video guide to locating the final three skulls in the new Halo 3 multiplayer maps included with ODST. In order for gamers to grab the final skulls -- and the Gamerscore attached to them -- players will need to enter each new map (Citadel, Heretic and Longshore) in Forge mode accessed on ODST's second disc.Like the Mythic Map Pack, not every skull is in an easy to reach location. Citadel may pose somewhat of a challenge, because the skull is placed in an area gamers may not be able to access when exiting Monitor mode. However, with the help of a few objects and the Grav Life equipment, it will eventually be yours. Found a better way to grab the skulls? Drop some science in the comments! Be sure to check out Joystiq's Halo 3: ODST Review, as well as in-depth analysis of the Campaign and Firefight games modes.