Mylia

Originally Posted by wikipedia

Player vs. Player

One major focus of City of Villains is the expansion of Player versus player (PvP) combat. Although PvP was introduced to City of Heroes prior to the release of City of Villains through the Arena combat system, CoV substantially expands the variety and importance of PvP combat.
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* For a short time, Items of Power were available after a supergroup completed the Cathedral of Pain trial. If a Supergroup's base contains an Item of Power, the lair is open to (scheduled) raids by any other Supergroup which owns fewer Items of Power. Items of Power confer modest stat bonuses to all members of the owning supergroup. The Cathedral of Pain trial, along with the Items of Power system, have been disabled for some time.
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Players can create bases for their villain groups. These allow the player to meet-up with other players privately and gain access to useful game facilities. From a base, players can travel directly to specific zones, buy Enhancements and Inspirations, or acquire missions, for example.

"Items of Power" can be stored here. These items provide the supergroup with stat bonuses, but also opens up the base for raiding (see also "Player vs. Player" above). The bases can be equipped with traps and other countermeasures to help fend off these raids. During scheduled base defense time periods any other supergroup will be able to raid the base and attempt to seize an Item Of Power. The trial to acquire Items of Power was disabled shortly after its release due to the presence of a game-breaking exploit. This left player-scheduled Base Raids with no rewards beyond bragging rights as the only avenue for base combat, until the Base Raid system was disabled in Issue 13.