Vigor (Classic)

Vigor is an talent in the Assassination tree. It increases your maximum Energy by 10. Combined with the glyph this increases rogue energy total to 120.

While the talent itself is gone, it's still alluded to due to the fact that merely being in Assassination specialization increases maximum Energy by 20.

Glyph of Vigor further increases its maximum Energy increase by another 10.

Nightslayer Armor, Gladiator's Vestments, Merciless Gladiator's Vestments, Vengeful Gladiator's Vestments, and Brutal Gladiator's Vestments each have a set bonus that increases their wearer's maximum Energy by 10, which can be stacked with Vigor and its glyph. An extra 10 or 20 energy is a serious advantage in any fight. If you know how to use it, you can be killer in PvP.

This talent loses its utility in raid PvE where the fights can last for over 5 minutes, having 10 more energy at the very start won't add up to any amazing raid dps considering you're bound to burn and regenerate several thousand energy during the course of the encounter.

• Vigor (The Hunt for Illidan), TCG card