The Stranger

The Stranger wears an invisible ring of mind shielding that thwarts magical attempts to read their thoughts. The Stranger also wears dimensional shackles but is eager to be rid of them. One touch from Omid's mace-key causes the shackles to fall off, freeing the Stranger.

The archmage has advantage on saving throws against spells and other magical effects.

The Stranger is an 18th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 17, +9 to hit with spell attacks). The archmage can cast disguise self and invisibility at will and has the following wizard spells prepared:

At will: disguise self, invisibility

Cantrips (at will): fire bolt, light, mage hand, prestidigitation, shocking grasp

Level 1 (4 slots): detect magic, identify, mage armor*, magic missile

Level 2 (3 slots): detect thoughts, mirror image, misty step

Level 3 (3 slots): counterspell, fly, lightning bolt

Level 4 (3 slots): banishment, fire shield, stoneskin*

Level 5 (3 slots): cone of cold, scrying, wall of force

Level 6 (1 slots): globe of invulnerability

Level 7 (1 slots): teleport

Level 8 (1 slots): mind blank*

Level 9 (1 slots): time stop

*The Stranger casts these spells on itself before combat.

Melee or Ranged Weapon Attack: +6 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 4 (1d4 + 2) piercing damage.