Tomb Raider Underworld had two cut characters; Professor Peter Eddington and his niece, Jessica.
There were plans of another artefact, the Eye of Odin, which resembled an articulated metal snake, which would wrap around the neck and head. It was going to possess Jessica.
A cut location was Arctic Drift Ice. It connected the two levels, Jan Mayen Island and the Arctic Sea. It would have given the all terrain bike more usage as well. Polar Bears would have been an enemy here. It was cut from the final game due to many reasons; it was too much to build compared to the actual gameplay that it provided and developers who made the maze areas often got lost so players would bound to also.
The all terrain bike had been designed so that the handle bars would detach and would function as a diver propulsion vehicle (DPV) but it was cut due to being difficult to handle in the underwater area that it was planned for.
There are 179 treasures to collect in Tomb Raider Underworld. Surprisingly, the Nintendo Wii and the Playstation 2’s versions have fewer treasures and no relics at all. In fact, the treasures are gold bars instead.
According to issue 126 of the official Playstation magazine which announced the PS4 version of Rise of the Tomb Raider, the total sales of Tomb Raider: Underworld on all formats is approximately 2.6 million copies worldwide.
Lara’s moves were motion captured by gymnast Heidi Moneymaker.
A few of the cheat codes from Tomb Raider: Legend works in Tomb Raider: Underworld, but this works only for the consoles.
The game has 21 levels and there are 185 secrets to find.
Lara Croft’s in game model contains 32,816 polygons.
After the level Croft Manor, there is a cutscene with Lara, Zip and Winston outside the manor. They watch as the Doppelganger jumps out of the large window. Lara came out of the main door below it, however this does not match up with structure of the building when inside the mansion in TRL- TRU as the large window is not situated above any doors but the stairs.
The health items vary depending on location. For example, in the isolated areas of Coastal Thailand, the only health item available is Health Goblets, you won't pick up a health pack. In Croft Manor, health packs are the only item available. The designs also vary to suit the location: on the ships, the health pack is a green box but in Croft Manor, the health pack is a rusted green box. The health goblets will also have a Norse, Asian or Maya design to them.