The Proving Grounds are a special type of single-player scenario that allows players to both learn and demonstrate the core skills associated with a given role or class. These might take the form of testing how long a tank can protect an NPC healer from a stream of oncoming enemies, or how much damage a rogue can deal to targets while avoiding awareness and movement checks of increasing difficulty. The system is intended to be a fun way for players to practice some of the skills that are essential for group gameplay, and for expert players to demonstrate mastery and compete for positions atop leaderboards, similar to the Challenge Mode feature.
There are three types of challenge, Damage, Tank and Healer, with each providing appropriate challenges. Each challenge can be tackled in Bronze, Silver, Gold or Endless mode, with each difficulty unlocked by defeating the previous one. Higher difficulties provide a stiffer challenge not only in terms of numbers but also in complexity, with more complicated sequences and combinations of enemies. Endless mode provides the player with a literally endless challenge, testing players to see how long they can withstand the onslaught.
The Proving Grounds become available at level 15, but only players at level 100 will be allowed to progress beyond Bronze difficulty.