The Comics: Lets get even crazier. Metron, a New God, sends a force that splits into four entities that are set up in different parts of the Milky Way. This evil force threatens to crash the universe by destroying planets. The Justice League decides to take matters into their own hands by splitting into four teams that go and face these monsters to save the galaxy. This story by Jim Starling and Mike Mignola, introduces cosmic fights galore where even the New Gods fight to see who ends up with control of the universe.
The Crossover: This is the most simple concept story out of all the suggestions I’ve added to this list, but this is the one with the biggest scale. The primary reason this story makes the list is because the set up is perfect. The writers can play mix-and-match with all their characters and split them into four teams. How many shows are going to crossover? Four! One of them is on Earth, so let Oliver Queen lead that team just like Batman led the Terran team in the comics. After that, the Legends, Supergirl, and Flash go off-world with meta-powers, futuristic tech, and alien forces to nail astonishing fight scenes.