Guardian Sanctuary is an active skill that can be taught to Priests at level 50. It cannot be ranked up at later levels.
Guardian Sanctuary can be performed with a staff by the Priest. It is not so useful in PvE, but it is a very powerful skill in PvP. The resistances make it easier for the Priest to kite melee characters and not be snared. The damage reduction is useful against powerful spells when all escape skills are on cooldown.
As of Apex changes Guardian Sanctuary also resets priest's Backstep, which allows priest to do quickly two iframes.
To glyph Guardian Sanctuary, a glyph must be obtained and learned only once. At level 60, a character has 50 glyph points available to spend on all available priest glyphs. Most glyphs, specifically common glyphs can be purchased from a Glyph Master, while fine glyphs must be looted from enemies.
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