QUOTE
You would generally use this Cloyster against Rhia's Crobat, or any other Pokemon that induces sleep and relies on Attack, like Breloom. But you'd especially use this against Rhia's Crobat, because it only has one actual damaging attack, and that's Pluck. Plus Icicle Spear would beat it out with super-effective STAB.
You make Doublehawk cry over its ugly teeth. :( SO THEN:
SteelixAbility: Sturdy
Curse
Flail
Gyro Ball
Earthquake or something more interesting
Item: Leftovers
Ideally, the Steelix would have extremely low Speed (and I mean low even for a Steelix) but really high Defense. Make sure its Attack and HP are decent, too. That's probably important. The idea is to use Curse a few times (two is a nice number), and then use Gyro Ball to just smash everything while you sit there invincible to everything that isn't Special. If you get low on HP by some crazy miracle (Counter would probably be the most likely thing to do that to you), use Flail until it gets recovered to decent health. I actually don't remember how strong Flail is, but I think I remember it hurting when low on HP. I just don't know when it would cease being more powerful than Gyro Ball. The fourth move should just be something useful. Like, I don't know. Maybe if someone sends out a Steel-type Pokemon. Because Gyro Ball and Flail aren't going to be that great against a Steel-type.
It basically counters anything that frequently uses physical attacks, especially if they're fast. But it's countered by CHANSEY WITH COUNTER and anything that uses special attacks, really. Slow things will be somewhat of a probem for it, as well, since Gyro Ball won't do as much. There I posted I hope you're happy Sauce. :(
BY THE WAY I THINK THAT IF ANYONE TRIES THESE OUT, THEY SHOULD SAY HOW WELL IT SEEMS TO WORK.