Scizor is really good in rain too. It takes care of the leads Azelf hates like flying black taunting fossils, countering Tyranitar, Scarfed Gengar/Latias, etc. You can weaken and scout teams with it and survive non STAB'd Fire attacks in Rain. It is long lasting with Roost so Stall doesn't beat you, and has a slow U-Turn to mimic an escape with Explosion so your sweepers are safe. =o