Please help me with my pokemon Y team?

I think you would go well running a sandstorm team. Reasons being is that Scizor and Gliscor are immune and Greninja can use a move which will make it immune. Don't worry about the Gengar, he's fine. Replace the Sceptile with a Tyranitar, then for your last slot, an Excadrill or Garchomp. I know what your thinking. Excadrill is Uber in a sandstorm, but fortunately, he is not in Regional Championships, so for worlds, just replace him with a Garchomp. Have your mega as Tyranitar if you want bulk, or the Garchomp if you want attack or Scizor for a bit of everything; whichever, it's your choice. Gengar you can use as well, but unfortunately his Mega is deemed Über in Worlds, just like sandstorm Excadrill. Have your Gliscor with the poison heal ability and give him a Toxic orb to hold. One thing I like about poison heal Gliscor is that he heals every time he is poisoned and you don't have to worry about other status problems.

If you are still worried about your Gengar in the sandstorm, just replace him with a Klefki up first with the Tyranitar and just set up with it, paralyse, etc..

Hope I helped!

i would go with Charizard, it's a strong fire type or go with Pangoro dark/fighting but with iron fist as it's ability