PvP, or Player versus Player is head-to-head mortal combat, pitting players against other players. The design focus of Diablo III's multiplayer is on PvM, Player vs. Monster cooperative play, but PvP will be supported as well.
game style means just that the primary opposition for a player in the game is other players. In the world of MMOs, the opposite of PvP is "PvE", Player versus Environment or "PvM" Player versus Monsters". For Diablo 3, terms like co-op is also often instead.
PvP in Diablo III
Unlike in Diablo II, there will not be any nonconsensual PVP in Diablo III; there is no more "hostile switch" or any other way to duel or PK in a normal game. PvP will be supported only in special dueling or arena games. There aren't yet any concrete details about how this will be handled, but more details will be released as the game moves through the development process.
D3 Lead Designer Jay Wilson talked about the D3 Team's philosophy towards PvP on August 20, 2008. [1]
- Jay Wilson: We'd like there to be a dedicated PvP mode, and we'd like to move away from [how it worked in previous Diablo games] where players just enabled PvP. We don't have any specific plans yet because we haven't really made any active decisions. The only real PvP-oriented decision that we've made and announced is that we do not allow the "hostility mode" that Diablo II had where you can go into town, go hostile, pop back through a town portal, and insta-kill your friend. That just makes people not want to play the game. I know some people say, "Oh, you're taking the teeth out of Diablo." I understand why they feel that way, but making people not want to play together does not make for a better game. That's our feeling.
- We definitely want there to be a PvP mode for PvP players, and we would like that mode to be a really serious, skill-based, very strong [aspect of the game]. I feel that on the side of all our games, we really try to make PvP games that cater to a competitive player, first and foremost. We don't try to dumb down or tone down our PvP games. We make [them] good, strong competitive games. StarCraft is one of the best examples. But in terms of what our actual plans are for Diablo III, we don't have anything to specifically announce right now, mostly because we're still messing around with a bunch of different ideas.