There are a few others, such as Swellow, Ambipom and Arcanine, even some Moltres as HP Grass and Will-o-wisp are relatively rare.
The only Normal attacker I can think of would be Swellow, but even there Rhydon is not as bulky as I would expect, Facade followed by U-Turn deals 48% average damage to 252/4 Adamant Rhydon (a defensive spread which I assume would be used on a CB variant). Which means that you are only coming in once, as after an initial Facade + U-Turn, two Facades will KO next time Rhydon tries to switch in.
Jolly Ambipom Brick Break vs 252/4 Adamant Rhydon: 30.92% average if holding Silf Scarf, 40.1% average if holding Life Orb. Granted, it seems as though less than half actually carried Brick Break in April. I'll buy this one, although it should be noted that, like Crobat, this guy likes to use U-Turn, and after seeing Rhydon will probably make use of it.
Arcanine, I'm not sold on.
Fire would be a cool resist if most Fire attacks weren't special and Rhydon's SDef wasn't total garbage. Its only real chance to wall Fire attackers is Arcanine, though Arcanine Fire Blast still does around 41% with no investment, so again you only switch in once, and you're always running the risk of HP Grass.
Rhydon's SDef is such that even resisted special attacks can cause significant harm to him. A Naive-natured Arcanine's Overheat and Iron Head do nearly the same damage to Rhydon, namely, both do amounts that are dangerously close to 50%. Add in the possibility of HP Grass; sure, most Arcanine don't carry it, but when they
do have it, your designated "Arcanine counter" switches in, ready to kick some ass, only to be instantly obliterated, game over, without doing anything, by the Pokemon it was supposed to counter. The consequences are severe enough that the move deserves to be taken into account despite a low percentage of use. WoW's pretty bad too: Unless you are running CB then Arcanine can survive whatever STAB move you hit it with after burning you, but even though Arcanine is almost dead, Rhydon is now almost equally worthless, as a burned physical attacker with 40 base speed threatens nothing and Arcanine is probably going to hit it with something else before dying.
In April, 39.9% of Arcanine carried Overheat, 17.6% carried Iron Head, 15.1% carried HP Grass, 11.6% carried WoW, 8% carried Fire Blast, 7.2% carried Flamethrower. The stats have a "10" in parantheses beside "Other" under Moves. Arcanine sets are quite varied; while there are certainly going to be variants that Rhydon can successfully counter, I don't feel safe just switching in blindly and assuming that I'm totally safe without knowing the set that I'm up against.
Moltres absolutely does not provide Rhydon with a safe switch-in. Even if they lack HP Grass, Flamethrower from offensive variants still has a very high chance to 2HKO. If it's a defensive SubRoost variant, then I will repeat that it is going to do exactly that, stall Stone Edge out of PP with Sub and then laugh at you.
None of those common fast, frail Pokemon want to be switching in on these guys
This is not true. Rotom can switch into Swellow Facades; Houndoom and Arcanine can switch into various Fire attacks; Rotom and Mismagius can even try to switch in on Ambipom. They run the risk that Ambipom carries Pursuit or Payback, but that's not so far removed from a Rhydon that blindly switches into Arcanine and just hopes that Arcanine has a set of Flare Blitz/ExtremeSpeed/Thunder Fang/HP Electric.
In any case, the reason that Rhydon can switch into a select few Pokemon which some "fast, frail" Pokemon cannot is because of its typing, which is totally non-existent amongst "fast, frail" Pokemon and thus provides Rhydon with a set of resistances which are not available to any of the "fast, frail" Pokemon. Just because its typing is different hardly means that it is better, though. While Rhydon can switch into Ambipom, Espeon can switch into Hitmontop, Mismagius can switch into Hitmonlee, Honchkrow can switch into Roserade, Swellow can switch into Torterra, Moltres can switch into Shaymin, etc.
Even "frail" Pokemon can afford to switch in once or twice on their resistances; it does not change the fact that they are frail. And if these are the only Pokemon which provide safe switches for Rhydon, Ambipom/Crobat/etc., then clearly this is all that Rhydon is able to do: Switch in on his resistances like the "frail" Pokemon, not his general "bulk" which you keep referring to. Rhydon is similar to all these "fast, frail" sweepers in that he hits like a train and switches in mainly on a revenge kill or on his resistances. The big difference is obviously that these other "fast, frail" Pokemon are actually fast.
Most of these Pokemon don’t necessarily like switching in to some of the common walls either, at the risk of getting paralyzed or in some cases hurt badly by an effective attack.
Yes, and Rhydon is not better than that. While Rhydon can switch into T-wave, Honchkrow and Primeape can switch into Sleep Powder or Hypnosis, and Arcanine/Houndoom/Blaziken/etc. can switch into WoW. While Rhydon can switch into Regirock without much fear (or can he? Nearly half carried EQ in April), he can't switch into other common walls, mainly Slowbro and Milotic, which other offensive Pokemon can. In fact, Rhydon is more likely to face super-effective attacks from UU's premier "walls" than most other attackers; Registeel has Iron Head, Regirock and Steelix can run EQ, Slowbro/Milotic use Surf. Again, he has traits that make him different, but not necessarily better.
But even ignoring that, I take issue with the way you keep saying ‘aside from Crobat’, as if Crobat is all of a sudden not an important factor when it comes to offensive synergy. I’m sorry, but the fact that Crobat is one of if not the most used Pokemon in UU right now, AND is the number one threat to typical offensive teams, means that it is an important factor, so stop pretending that it isn’t.
As I said earlier in the topic:
Okay, the Flying resist is notable because of Crobat alone.
I acknowledge the importance of a Crobat resistance in the current metagame. I'm not seeing it as a saving grace for Rhydon because of the original argument from which this sub-argument has branched off: Is Crobat BL? The fact of the matter is that, if Rhydon must use Crobat's prevalence as a crutch to support its viability, that implies that Rhydon would not be viable if Crobat were not overly popular; this, in turn, implies that Crobat is indeed overcentralizing the metagame, and that Rhydon is indeed a specialized Pokemon which is not generally fit for use outside of countering Crobat. Overall, I'd say that supports the "Yes, Crobat is BL" side of the argument.
The reason we are failing to get anywhere is that you continue to be adamant in your belief that Rhydon cannot work well offensively, despite all the reasoning me and others have given that refutes that claim.
Or the reason we are failing to get anywhere could be that you continue to be adamant in your belief that Rhydon can work well offensively, despite all the reasoning I have given that refutes that claim. So what? Argue the point at hand or don't, but either way don't waste time pointing fingers at the other side because they don't agree with you, as that accomplishes nothing.
It has become such a digression from the main point, which was that offensive Rock types can have a use on offensive teams to keep Crobat (and possibly some other things) in check, and there is nothing wrong with that.
Rhydon's the most viable offensive Rock-type I can think of (which says something about the viability of offensive Rock-types in UU overall, I think), besides maybe Relicanth, so this is quite relevant to that issue, I believe.