Welcome to Smogon! Take a moment to read the Introduction to Smogon for a run-down on everything Smogon, and make sure you take some time to read the global rules.
I am honestly quite surprised this did not happen earlier. I have abused this monster for months now, with Skymin carrying my team to a massive ELO of 1200+
Hi!For your first question, the most used lead because it works in ubers is deoxys-s. I would recommend the following set. I feel that the best pokemon to switch out for deoxys is kyogre,as Ryan's suggestion of specially defensive jirachi fills kyogre's role on the team.
(Deoxys-Speed) @ Focus...