You can't end a long D&D campaign by having your party fight Steve, Local Janitor Who's a Bit Skeevy. No, you need something truly epic. But if you're having trouble coming up with some sort of epic end-antagonist, 2CGaming is here to help with Epic Legacy: Tome of Titans, a new RPG supplement up on Kickstarter now.
From the campaign:
Behind every great 5th Edition campaign lies a great antagonist. The Epic Legacy Tome of Titans exists so your table will never be without the most iconic, powerful, and challenging enemies from fiction, mythology, and RPG lore. Asmodeus, Cthulhu, and the Angel of Death are among these deadly foes we call titans, and they are guaranteed to be the mightiest monsters to ever grace your game table.
The campaign's headed towards 3x funded with 37 days left to go.