Archmage

Medium humanoid (any race), Any alignment

Armor Class12, 15 with mage armor
Hit Points99 (18d8 + 18)
Speed30 ft.
STRDEXCONINTWISCHA
10 (+0) 14 (+2) 12 (+1) 20 (+5) 15 (+2) 16 (+3)
Saving ThrowsInt +9, Wis +6
SkillsArcana +13, History +13
Damage Vulnerabilities—
Damage Resistancesbludgeoning, piercing, slashing (from stoneskin)
Damage Immunities—
Condition Immunities—
Sensespassive Perception 12
Languagesany six languages
Challenge12

Traits

Magic Resistance.

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

Actions

Dagger.

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

Spellcasting

The archmage 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: 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