I would definitely like to see a game mode in the Crucible featuring Guardians vs. Taken Guardians (much like the infected modes in CoD or Halo) where you could play as both a regular Guardian and a Taken disciple of Oryx. The Taken Guardians would be outfitted with very unique/dark abilities (maybe modified subclasses or just a controlled loadout for each player) while the other Guardians would have to defend themselves from their "turned" comrades, or face being Taken themselves. This seems like it would be a very fun game type that would be a great addition to Destiny (if it's even possible with the current standing of the game).