Aura of the Merciless

 is an active skill that can be taught to Mystics at level 50. It cannot be ranked up at later levels.

Rank table
To obtain, one must find a Magic Instructor and pay a certain price of gold.

Glyphs
To glyph, a glyph must be obtained and learned only once. At level 60, a character has 50 glyph points available to spend on all available Mystic glyphs. Most glyphs, specifically common glyphs can be purchased from a Glyph Master, while fine glyphs must be looted from enemies.

(Disclaimer: As NPC shop prices vary depending on a variety of factors, the prices below are subject to variation. Only take them as benchmarks.)