There is nothing quite like a villain losing the one person they love the most. Oh they were evil, vile, sadistic and cruel for sure, but they had a soft tenderness with their beloved. Bonus points if the beloved was just as evil as the villain, or the beloved didnt care that the villain was evil and loved the villain with their whole heart.
Oh and if the death of the beloved is directly or indirectly caused by a fight with the Heroes. Oh thats delicious, sweet angst that basically has the villain on a crash out.
'I have nothing left to lose... and I am going to make it EVERYONE'S PROBLEM". If they wanted to rule with their beloved? now they want to destroy the world because its not worth having if the one they wanted to rule with isnt there.
Evil love ending with tragedy. Delicious and tasty. Let that sorrow and rage make the Villain unlock a new power or go full power. Thats when its peak
