Talk:Quotes and Dialogue (TR7 onwards)
Here is a list (and there are many more sites I could add) that refer to Underworld as the ninth game, or the ninth episode, or the ninth version, or whatever;
http://technology.iafrica.com/games/xbox360/1426540.htm
http://games.kikizo.com/reviews/ps3/tomb-raider-underworld-p1.asp
http://bygonederbyshire.co.uk/articles/Tomb_Raider_%E2%80%93_The_classic_video-game_created_in_Derby
http://theuntechieblog.wordpress.com/2008/08/23/lare-croft-crotch/
http://www.acegamez.co.uk/reviews_ds/Tomb_Raider_Underworld_DS.htm
http://download.chip.eu/en/GC-2008-HD-Trailer-Tomb-Raider-Underworld_3611230.html
http://www.eurogamer.net/articles/tomb-raider-underworld-dated
http://www.lawrence.com/news/2008/dec/29/tomb-raider-underworld-360/)
Tomb Raider Wiki refers to Underworld as the "8th". So does the Wikipedia entry, but that's been taken over by the same people who write for Tomb Raider Wiki, and therefore does not count as an official source of information.
I've tried to find an official pronouncement about the game numbering on various official Eidos sites with no luck, so if anybody can find one - that'd be good :)
Ostercy 010309