The glyph dungeons are located in Dragonmist Island and are the best place to obtain high quality glyphs.
Benefit Dungeon[]
The Benefit Dungeon is the home of the Legendary Fire Golem: a tanky boss that does damage based on it's HP. The lower it's health becomes, the more damage it does. It also begins to regenerates health if it takes a turn while below 25% HP.
The monsters found in the waves of this dungeon are tanky units that are hard to kill, but largely don't do very much damage.
Wrath Dungeon[]
The Wrath Dungeon is home of the Legendary Water Griffin: a hard hitting AOE attacking boss that shields itself if it lands a critical hit on an enemy. It also has an attack that life-steals from enemies hit.
The monsters found in the waves of this dungeon are relatively easy to kill attackers that do large amounts of damge.
Strength Dungeon[]
The Strength Dungeon is the home of the Legendary Howling Spectre: a hard hitting boss that applies a great deal of debuffs. This boss is the only one of the Glyph Dungeon bosses that doesn't have sustain, but it gets immunity each of its turns, which makes it hard to kill. It also applies poisons and blinds to enemies.
The monsters found in the waves of this dungeon are moderately tanky, and apply debuffs to enemies in order to kill them.