From Guild Wars Wiki
- Concise description
In Player vs. Player maps, some skills behave differently. Altered skills have "(PvP)" added to their names.
- This effect is only bestowed while in a PvP outpost.
- This causes certain skills to behave differently in PvP for the sake of skill balance.
- The List of PvE and PvP versions of skills shows both versions for comparison.
- This prevents the use of PvE-only skills.
- If you call this effect, you will say "This is PvP!" in the team chat.
- This effect was added in the May 22, 2008 update.