Total Nightmare Invasion

NOTE: Only Final Bosses Can use this! Players can't Use this Spell Unless they become the Final Boss of the campaign AND Learned it. Also It takes 30 Nights to cast this.

THE DM THEMSELF has to make a DC 90 Save or Force a wish spell to stop the Spell's Creator's Old Nightmares from Invading the Campaign's world. (Low tier Nightmares Are CR 900, Medium Tier Nightmares are CR 1,000 And top tier Nightmares are CR 9,001 and this kind can only be killed With the spell's Creator's Super weapon Named Nightmare's Bane That Happens to be sent to the world By It's Creator.)

(DM's! Use this for plot, Like a time Limit or something!)