BnE, no offense, but most of those are great checks for several reasons:
1) Toxicroak- So Gorebyss can come in and use Psychic, but that gives Honchkrow/Dark Type a free switch in because it's not only completely transparent what he's going to do because that's the only attack they carry that can actually do damage to him.
2) Milotic - Grass Knot doesn't really hurt it too much, even coming from Ludicolo, Energy Ball hits harded, and I haven't done the calcs on this one, but she can check most rain sweepers easily.
3) Golduck- it wastes turns of rain, but not much else...I've never used it so I'm not entirely sure.
4) Registeel - Paralyzes tops after it takes a hit (yeah, it's 2HKO'd but w/e) paralyzes Ludicolo and Gorebyss with little difficulty. Probably one of the main reasons why Rain teams want to run Dugtrio, immune to T-wave + traps Registeel.
The rest are iffy, and one isn't mentioned: Lanturn.
Lanturn can't take a boosted hit from Tops, obviously, but it can easily switch in to any special sweeper, has 4x resist to water, access to STAB Thunderbolt, Thunder Wave/Confuse Ray for parafusion, and high SpD to boot. It can stop a rain team in it's tracks by nullifying their speed advantage with T-wave and threatening with a STAB electric attack.
Edit: Also, Kabutops suffers from 4 moveslot syndrome: it needs SD and Stone Edge, then you have to choose between X-Scissor for Umbreon/Megnanium/etc, Return for neutral coverage, Aqua Jet to beat Priority, Earthquake for Registeel, and Waterfall/Aqua Tail for a rain boosted STAB.
Ok so I'm going to call bullshit on like all of this post.
1. Yeah ok you've got me on that one, Honchkrow can come in on Psychic and threaten with Sucker Punch... But it can't hope to OHKO without both Stealth Rock and a round of Life Orb damage under its belt so you're still losing Honchkrow just to stop Gorebyss from sweeping. And even still, if you're willing to accept this as a viable check then we get into this weird mumbo jumbo about how you can bait attacks and go to shit that can revenge and I really don't think that's where we want to go with these arguments... and if you really want to get scientific about the whole process, we could go to the teammate stats and see that Honchkrow isn't even near Toxicroak's favorite teammate to be paired with so it's not unlikely that you would see toxicroak without Honchkrow on the same team... Not to even mention that it's very likely that we'll be saying goodbye to our Avian friend, so the use of him in any argument is a bit reaching if you ask me.
2. Ok so first of all, Grass Knot hits Milotic for 100 Base Power. I know this because I constructed a handy little chart for this page
http://www.smogon.com/dp/moves/grass_knot that I expected people to look at before spouting out obvious bullshit like "Energy Ball hits it harder". Also, exactly what Rain Sweepers is Milotic checking again?
Kabutops' Swords Dance Life Orb Stone Edge versus Max / Max Milotic
722 Atk vs 282 Def & 394 HP (100 Base Power): 358 - 423 (
90.86% - 107.36%)
That's an OHKO nearly 70% of the time with Rocks and Leftovers.
Qwilfish obviously 2HKOs with a Swords Dance Poison Jab, and to be quite honest, that's all it needs to do, especially because Hidden Power Grass is the overwhelming favorite compared to Hidden Power Grass (37% :: 9%), and even if it does run HP Electric, it fails to OHKO Qwilfish (only does at max 71%).
So really, there's only one Pokemon on a Rain team that Milotic DOES wall, and that's Gorebyss (not including Omastar because I find it to be worthless in today's Rain Dance teams).
3. Golduck is utter shit and shouldn't be used, and the evidence for this is the fact that it ISN'T used. There's a reason it's NU, and not being "discovered" for being a great Pokemon isn't that reason.
4. The most popular variant of Registeel is by far 252 HP / ~126 SpD / ~136 Atk. Only 7% of all people ran a Def+ Nature on Registeel last month. Kabutops easily OHKOs the most popular variant of Registeel.
722 Atk vs 336 Def & 364 HP (80 Base Power): 360 - 424 (
98.90% - 116.48%)
5. (your edit)
Kabutops in no way has 4 moveslot syndrome. All it needs is Swords Dance / Stone Edge / Waterfall / Aqua Jet.
There is not a single set in the analysis for Umbreon that recommends ANY Defense EVs. And Kabutops easily OHKOs with a +2 Waterfall
722 Atk vs 256 Def & 394 HP (80 Base Power): 471 - 555 (
119.54% - 140.86%)
Similarly, Meganium is OHKO'd 74% of the time with just Stealth Rocks, so there's really no reason to run X-Scissor ever. Especially considering that X-Scissor doesn't OHKO anything notable (it'll never OHKO a Tangrowth, you're better off trying to get a single layer of spikes and Stealth Rock on the ground and hitting it with Stone Edge, since that will OHKO too)
722 Atk vs 328 Def & 364 HP (100 Base Power): 306 - 361 (
84.07% - 99.18%)
Also, Kabutops doesn't learn Earthquake, and there's no reason ever, EVER, to run Return because it's a shit move.
tl;dr - d2m try and put some thought into your posts.