Dark Sun

Your character, having given up the ability to cast spells forever, uses all his powers to create a giant sphere. The sphere uncontrollably absorbs all magic within 20 km, making it impossible for creatures to use or cast spells. The sphere blocks access to the invocation and spells of all schools. All beings within a radius of 20 km must succeed in saving the Physique 15, in case of failure, it, like the creator, will forever lose magical powers and the ability to use magic.
Every creature within 20 km must succeed in an Intelligence saving throw of 15, in case of failure, the creature will be split by dense magical vortices.
The Dark Sun increases in size within 1 hour after casting the spell . After 1 hour, the created sphere explodes, causing a fixed 500 (50 d20) physical and magical damage to all creatures within a radius of 100 km.
The area within 100 km, after the explosion, becomes a dead zone in which magical anomalies run rampant uncontrollably.
If your character is a Sorcerer, then instead of losing magical abilities, your character dies.