Tekken: Dark Resurrection is an updated version of Tekken 5. It is based on the updated version of the arcade game, known as Tekken 5: Dark Resurrection or Tekken 5.2.
There are numerous changes and additions. For instance, Armor King and Panda are now characters in their own right, rather than re-skins of King and Kuma, there are two completely new characters, several characters have custom colors on costumes, you can combine multiple customizations on a body part, all the stages have been changed to a different time of day with new set-pieces (the original versions are unlockable), there are new moves, new ranks, and auras change color to reflect ranks.
There are also several new modes. Tekken bowling returns from Tekken TAG Tournament, there is a new dojo mode where you unlock most of the unlockables, and a gold rush mode to get rich quick. The biggest addition is ghost mode. You can record a fighting sequence, then upload it to he the internet so players around the world can download and play against it.
