Archmage

5e compatible shield

Medium humanoid (any race), any alignment

Armor Class 12 (15 with mage armor)
Hit Points 99 (18d8 + 18)
Speed 30 ft.

STR DEX CON INT WIS CHA
10 (+0) 14 (+2) 12 (+1) 20 (+5) 15 (+2) 16 (+3)

Saving Throws Int +9, Wis +6
Skills Arcana +13, History +13
Damage Resistances 
Damage Immunities 
Condition Immunities 
Senses passive Perception 12
Languages any six languages
Challenge 12 (8400 XP)

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

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 ““ and ““ at will and has the following wizard spells prepared: Cantrips (at will): ““, ““, ““, ““, ““ 1st level (4 slots): ““, ““, ““ 2nd level (3 slots): ““, ““, ““ 3rd level (3 slots): ““, ““, ““ 4th level (3 slots): ““, ““, ““, ““, ““ 6th level (1 slot): ““ 7th level (1 slot): ““ 8th level (1 slot): ““ *The archmage casts these spells on itself before combat.

Actions

Dagger. Melee or Ranged Weapon Attack: +6 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 4 (1d4 + 2) piercing damage. Archmages are powerful (and usually quite old) spellcasters dedicated to the study of the arcane arts. Benevolent ones counsel kings and queens, while evil ones rule as tyrants and pursue lichdom. Those who are neither good nor evil sequester themselves in remote towers to practice their magic without interruption. An archmage typically has one or more apprentice mages, and an archmage’s abode has numerous magical wards and guardians to discourage interlopers.