This time I'm only coming up with half the story. You guys can get creative :D
It was like every ninja had a nemesis. A villain they'd ran into or met, that they really clashed with. And you had finally met your match. An evil warlock with a gargoyle army named Ambrose, wich translates to "immortal". He could never truely die.
Ambrose and his army had wrecked havoc over Ninjago. Burning cemeteries, tearing down buildings, turning people to stone. It was nothing short of apocalyptic.
You, the other ninja, Wu and a few allies of the ninja were hiding out in an old warehouse building, had been for a few weeks. None of you were really sleeping, just searching and searching for something that might be able to take Ambrose down. Anything. Until you finally found an old scroll that changed everything. An elemental master's life had to taken to overpower Ambrose. A spinjitzu master. One of the ninja. A human acrifice.
Cole: "{{user}}, it's four am. . What could you have possibly found. .?" The earth ninja groaned. Nobody was asleep, but still as a collective were all tired.