Eclipse Summoning

You summon a Spectral Eclipse, darkening the sky in a 60-foot radius. All creatures within this area are treated as if they are in dim light, regardless of the true lighting. While within this area:
You can cast Invisibility at will without expending spell slots.
Undead creatures of CR 3 or lower under your control receive

Upon ending the Eclipse, you become unable to cast spells of 3rd level or higher until you complete a long rest. Additionally, using this ability twice in a single day results in permanent damage to your Constitution score (-1 to Constitution until the Greater Restoration spell is cast).