Void Archmagus

Arcane Constructs: At critical health, the Void Archmagus summons massive void-imbued arcane constructs—towering golems made of enchanted obsidian that serve as guardians, making the fight even more perilous.

Absolute Curse: The Archmagus places a permanent curse on players who get too close, draining their XP over time and preventing healing from traditional means.

Weakness:

Only enchanted gear of the highest tier can damage it. Coordinated attacks targeting its core can destabilize its form, leading to its eventual defeat.

Reward:

Ultimate Enchanted Book: Enchantments like Fortune III, Mending, and Sharpness VI are possible, pushing the limits of standard gameplay.

Tome of Infinite Knowledge: Grants access to a spellcasting system, allowing players to wield powerful arcane magic.

Voidheart: An item of immense power, allowing players to create void portals or summon void creatures as temporary allies.

Abilities:

Arcane Cataclysm: The Void Archmagus unleashes a catastrophic storm of arcane energy that decimates the landscape. Players caught in this storm are bombarded with a combination of lightning, fire, and void energy that burns through health and gear durability.

Void Collapse: The Archmagus has the power to collapse sections of the world into the void, turning areas into unstable, floating islands where gravity no longer functions properly.

Reality Break: This spell shatters reality itself, causing the world to glitch, blocks to flicker, and players to experience random teleportations, stat changes, or inventory scrambling.