• Kyle Gass reference

The man at the mortar missions has the same facial features as Kyle Gass, the other member of Tenacious D, Jack Black's band.
  • Post-completion interactions

Successfully complete the game. Search the indicated locations to find the following characters to have a final interaction with them.

Fire Baron: He can be found in the jungle directly north of the tree island at the bottom of the last continent. He can be found to the left of the main road as soon as it turns, traveling south to east.
Infantry/Army: At the Bladehenge beach party.
Lita: Visit the graveyard located in the first grassland portion of the map near Mount Rockmore. You will find Lita kneeling by her fallen relative's headstone. Press [Interact] to view a brief cinematic and share a moment of silence with her. The moment will last and the time of day will shift until you press that button again.
Kill Master: Patrolling on his motorcycle on the highway north of Bladehenge.
Mangus: On top of the large sword in Blade Henge. Note: Use the nearby Landmark Viewer.
Ophelia: Return to the large stone cross in the grasslands area (located to the left of the massive sword on the map). Near the landmark viewer, Ophelia is sitting in front of the stone cross. Press [Interact] and Eddie will ask if she wants to make out. A cinematic will play of the two kissing until you press [Interact] once more.
Rima: On top of her towerin the jungle.
Thunderhogs: At the Kill Master's Lair. You can drink with his bassists and comment on Lemmy's bass playing ability.
  • Psychonauts reference

In the first cinematic, where it gives you the options to toggle the blood gore and swearing, wait until just before Eddie says the line that would lead to the option of turning on or off swearing. He sees one of the band members dancing on a very shaky ledge. While that band member is dancing on that ledge, he will be chanting a little song that was done in Psychonauts by a few kids in a few parts, but more notably by Raz himself in the level where you have to face four wrestlers to get a card. At the end of each match after you defeat them, Raz did the same dance and chant the song.

The headbanger that wears the goggles at all of the Death Rack missions sounds identical to Raz, but slightly deeper.
  • Ride the wildlife

Every animal as big as Eddie or larger can be taken for a ride. Zap the creature with a bolt of lightning to stun him. Then, approach closely and press Triangle. While riding, press X to perform an attack specific to that creature. Raptor Elk and Tullusks are just a few examples of creatures with melee attacks, while the Laser Panther shoots lasers from his eyes. Although it may not seem by their stature, the large wooden horse creatures in the final map area (with large swinging axes for tails) can also be stunned and taken for a ride.
  • Rob Halford reference

Rob Halford plays General Lyonwhite even though his last name is Lita and Lars'.
  • Steel-Quill Axe

Complete all of the Hunter secondary missions. Note: The Hunter is located near the stone cross in the grasslands, and will relocate halfway through his missions to the ice barracks. Afterwards, return to the first place you met him and he will reward you with a Steel-Quill Axe.
  • Triple nitrous power

Successfully complete all the Racing Missions.