[quote=@Savo]Lets say hello to Terry and Jerry, both are trainers in the rp. Terry didn't reserve any legendaries, however Jerry did. Terry is up against a long gruelling battle against said legendary and when the time comes to catch it...

1. Jerry ninjas it from him with another pokeball, making hard work hardly work. Sure, it can lead to some character development, but it depends on what the characters are like.
2. Terry catches it, but Jerry takes it since he reserved it, making it the same situation as before in a way.

[/quote]

The Pokemon they reserved, will fight the one who reserved it. 

Say we were in the Kalos region. You go to the tower of mastery, because your curious. There is an old man here who tells you about a Pokemon that flies here sometimes from azure bay. He senses a strong aura off of it. 

Then you can go to azure bay. It won't just be that, there will be obstacles in the way of your getting there.

 When you reserve the legendary, there will be an event or quest you have to do to find it, then battle it.

Get it?