Archmages bane

Arcane Restoration. If the archmages bane dies it reforms one hundred miles away from where it died in 1d10 days.

Greater Magic Resistance. The archmages bane automatically succeeds on saving throws against spells and other magical effects, and the attack rolls of spells automatically miss it. Without the archmages banes permission, no spell can observe it remotely or detect its thoughts, creature type, or alignment.

Reactive. The archmages bane can take one reaction every turn of combat.

Regeneration. The archmages bane regains 15 hit points at the start of its turns.

Multiattack. The archmage makes three Arcane Burst attacks and uses nullify magic.

Arcane Burst. Melee or Ranged Attack Roll: +12, reach 5 ft. or range 150 ft. Hit: 28 (4d10 + 6) Force damage.

Spellcasting. The archmage casts one of the following spells without requiring verbal or material components using Intelligence as the spellcasting ability(spell save DC 20):

At Will: Detect Magic, Dispel Magic, Detect Thoughts, Disguise Self,silence, Invisibility, Sending, Clairvoyance, Mage Hand, Prestidigitation
3/Day Each: Dimension Door, Lightning Bolt (level 7 version) Greater Invisibility, Scrying, Modify Memory,
1/Day Each: Cone of Cold (level 9 version), Forcecage, Time Stop, Teleport Disintegrate, Feeblemind,

Nullify magic. The archmages bane targets one creature that is concentrating on a spell or magical effect that creature then has to make a contested arcana or religion check against the archmages banes arcana. If the creature loses their concentration ends.

Misty Step. The mage casts Misty Step, using the same spellcasting ability as Spellcasting.

Protective Magic. The archmage casts Counterspell or Shield in response to the spell’s trigger, using the same spellcasting ability as Spellcasting.