There currently are two game pages, titled Severance: Blade of Darkness and Blade of Darkness which as far as I can tell are the same game. There are slightly different (by a couple of days, all in February of 2001) release dates associated with the games.
As far as I can tell, the game was released under a few different names, which I guess may have caused the confusion, it was originally released in Spain under the name Blade: The Edge of Darkness, which was changed to Blade of Darkness when it was released in the US, as the original title was too similar to the Blade TV show and movies, and was later released in the UK and the rest of Europe under the name Severance: Blade of Darkness.
Currently the Severance: Blade of Darkness has more content than the Blade of Darkness page, but I guess the common policy on Giant Bomb is to use the most common US release title as the page name, so I'd suggest that the content of the Severance: Blade of Darkness page be merged into the Blade of Darkness page.
The Wikipedia entry for the game: http://en.wikipedia.org/wiki/Severance:_Blade_of_Darkness (which seems to imply that the longer title, Severance: Blade of Darkness, was also used in the US, but it doesn't get very specific about it), the MobyGames entry at http://www.mobygames.com/game/windows/blade-of-darkness shows the cover art for the US release where the title is just "Blade of Darkness", and lists Severance: Blade of Darkness and Blade: The Edge of Darkness as European variations.