This is a little side story between When Black and White Worlds Collide and When Black and White Worlds Collide2. This is when Arceus decides to create the DNA Link Key(and creates a chain of events that fuse a particular Pokemon), enjoy
In the Hall of Origin in the well known region of Johto, Arceus was trotting around, quite bored in his cell-like chamber.
Then the stairs appeared(which meant visitors) and Kyurem with Zekrom pranced in, looking at the creature. 'Arceus. How are you?'
'Good,' snickered Arceus as he thought up a device. 'Give me your ice shards on your back paw, Kyurem, Zekrom, give me a strand of your coal like fur.'
'Why?' They both answered blankly.
Then Arceus pushed them together and created a link key, putting the deadly needle inside both their bodies.
'Noooooo!' Kyurem and Zekrom let out a blood-curdling scream that echoed through Johto endlessly.
Humans and their Pokemon stopped and listened to the scream for help, hearing only a faint shout and a poof.
In the Hall of Origin, a new creature was created.
What did I do, wondered Arceus as the creature scratched him to bloody shreds…