Welcome to Hell (BatIM x Hazbin Hotel crossover/Male Reader insert)

Chapter 26: The last prayer

Three keys.

He lost three of his keys already.

The first one, stolen by the wrong angel and her lapdog inside is own vault.
The second one, handed over by the true believer after the destruction of his warmachine.
The third one, taken after the final destruction of Bertrum's nightmare ride.
Now there is only one key in his possession, guarded by the fallen Angel herself. He told Alice that failure will not be tolerated, she will give her life to protect the last key. Or at least, thats what he think she would do. But the truth is that Alice and his Lost Legions infront of her Cathedral will only buy him some time. Nothing more.
He tried nearly everything to defeat (Y/N) and his Demons. He tried to corrupt him, to pull him on his side and he failed. He sended Legions of his undead hordes against him, they never came back. He tried to blow him up, but he survived. Sammy failed. Bertrum's machine failed. And Alice will fail too. But to be fair, no one knew that (Y/N) is actually a fucking Demon. No one knew, not even (Y/N) himself, that this young lad with a nearly everlasting smile was chosen by Lucifer himself. Maybe the blue suited stranger was right. Maybe Joey took it too far. Joey created his own version of Hell, his own Demons. And with that, he got the attention of the dark lord himself. There can be only one Hell. Lucifer sended the blue suited stranger to find a soul that was already "corrupted" in a way. And so he found (Y/N), a young man who tried his best, a person who had no reason to smile, to laugh or to be happy in general. New York City wasn't really a nice place in the Prohibition years and (Y/N) needed to find it out the hard way. But he also couldn't return home. This was not a option for him.

He was the one Lucifer was looking for.

A deal was made with the young man while the blue suited stranger worked as a middleman. On this day, the young man reached his full potential. On this day, Lucifer himself granted the young man with a gift.

The powers of the Devil.

The powers of Chaos under his command. But of course, (Y/N) didn't know this at the time. He only knew about all of this a few days ago. And yet, he gained control of his unholy powers in just a day or two. Not just to destroy Joey's Machine and his monsters, but also to protect the people he loves.
Joey knew about his powers, a Lost scout has informed him about that.
He sighes. He stands on his balcony, hands on his back. What to do? What to do? Joey's only hope to defeat the Devil is to complete 'Project Ascension'. To unleash his Final Sin and then use all the power of his Dream Machine to rise. To ascend out of his old Studio.

But only time will tell if the traitor actually succeed with his plan.

Joey turns around and walks towards his throne.
He sits down, closes his eyes and put his hands together. He pulls his hands towards his face and then starts to pray.
He prays to the unholy powers who granted him all of this in the frirst place.

The young Demon looks at the keys infront of him. They are laying on the table on top of Allison's map.
One is missing. And he knows exactly where they get it. Allison walks up to him,

AP: "Well. I think we all know where we get the last key."

The rest of the alliance joins in and stand now at the table. All except one,

A: "Uh, has anyone seen Niffty?"

V: "We gave her a scouting mission. We need all the information we can gather befor we attack Alice's Cathedral."

Like on cue, the vent above them breaks. And Alastor catches Niffty again without looking,

AL: "Hello my dear. What do you have for us?"