So Sandslash is a main focus of the team, and so I try to save him until the end of the game, along with dugtrio.
Digtrio is my sand setter. I know you pribably think I am crazy, but let me explain. With Dugtrio'd high speed, it is almost guaranteed a free sandstorm, and if somehow it lives, it can utilize his sand force.
Tyrantrum is there, so I can have a revenge killer, and so that I can kill mons in and out of sandstorm. Simple and Standard.
Sigilyph is there, as a special wall, and status soaker. I originally was going to add venusaur, but venusaur does not lile sand much. Sigiliypj does not need to run Energy Ball, as you can replace it with what you need, as I had tailwind before energy ball.
Steelix is fairly standard, but he can utilize sand force if needed, and sets up rocks and toxic.
Seismitoad is my water wall. He can take all of the water moves with water absorb, and then he gets sludge wave, and ither cool coverage along with good stab. You could run hydro pump> scald, but up to you.