Alright, so I took some flak for what I believe to be the top 10 mons to use on a stall team right now. Most of it I shrug off because honestly I respect five or six people to know more than I do on the subject and none of them have said anything about it (p2, like Electross and Sassy chomp, are kinda my own projects where people like Yutt constantly use alomomola, Aggron, manatine and the likes. We'll give each other advice on them but generally let each other hold their own opinions on their viability).
Now, the list, for reference, was: MVenu 1, Chansey 2, Sylveon 3, Skarmory 4, P2 5, Heatran 6, Chesnuaght 7, Quag 8 (too many bulk flaws), CharX 9, Clef 10. I'll go through all of them. In all honesty, I might even have thrown Aggron-mega up as well. I'm going to explain it and see if anyone wants to critique. To be honest, the only people who venture through this thread are the ones who play stall so I don't have to worry about irrelevant opinions as much.
1. Mega Venusaur.
jbtc10 wanted to state that ZardX and Venu are different, but venu isn't as important as we think... Well. The first is easily correct, second is not. While venu holds a different niche than Amoongus, I never compared them and to be honest, Amoongus is kinda hit/miss on it's own role (can't stop BD azumarill).
But, Venu is as important as we say. The reasoning? Well, it walls so much. While that seems like a copout, it is hard to nail down what exactly Venu's purpose is, which is why I referred to it as a cornerstone. It is something that you can use and build teams around with ease. Apparently a formula has been found, but once venu is in, the question isn't "What do I wall next", it's literally "What did venu miss?". Venu misses Flying types, Psychic types, Landorus, Kyurem and a few others. Very, very high level look obviously. But let's face it, I wouldn't be making a terrible stretch to leave it at that. The flying/psyshic/fire/ice kinda issue are all solved with heatran, which is why he was ever USED on stall. Heatran is not important, please understand. We'll get to that, but heatran is simply there to support venu.
2. Chansey. While again jbtc wants it as #1 (which, you could make an argument for), think of it like this: Venusaur is a high wall for 75-90% of the meta. Chansey is nearly an insurmountable wall for 50%. There's a difference in what you need. Obviously, chansey's team support is invaluable, but it is not the only one in the world that can give that. Alomomla drops wish bombs, Sylveon doesn't do bad, and oddities like Heal bell meloetta/clefable/whatever you find it on do exist. Chansey is HARD to replace. Venusaur is IMPOSSIBLE. There simply is nothing that does what he does, as his typing (grass/poison) is deceptive as hell. He doesn't have grass standard weaknesses. In fact, a type to think of venu is Fighting when viewing his only weaknesses and steel when viewing resists, taking none of those weaknesses and none of fight's resists into account.
3. Sylveon. Oh let the rage begin. First off, there is no way anyone who has EVER used stall could confess Clefable to be a better cleric. Simply impossible. Secondly, Sylveon provides, outside of Mega Gardevoir who is questionable for stall, the third most fire power provided by any stall mon (aegi is above, heatran is barely above iirc). That forces switches. Which means turns, leftover recovery and wish passing. But more importantly, it has stats that you NOTICE. Clefable can't attest to that, but clutches to unaware. Sorry, really good stall players can get by without unaware in MOST situations. The "Most" part is where you do use Clef. Besides chansey, it is the only cleric that should ever be built around.
I've written that post on it, just going to link it. Same thread obv.
4. Skarmory. Skarm used to be like chansey in the fact that it was a nigh insurmountable wall for 50% of the meta... and then power creep. Well, Skarm has three major roles this gen that are nigh irreplaceable. 1. Walling Pinsir-mega. This is now slightly less important, but it takes +3 mega pinsir so room for fuckup is there. Counter/taunt is nice. 2. Defog OR hazard setting (the first major distinction from Zapdos). It gives you maneuverability to find a hazard setter/clearer and allow skarm to take the other role. Most commonly, skarm defogs as it is the
single best defogger in OU. 3. Azumarill check. While it doesn't take BD azum, it can sure wall the monster CB Azum, and quag can take the BD anyways so w/e. These roles are important, but number 2 is the reason it has this spot as the other two are solvable otherwise.
5. Porygon2. People love to hate this one, but let's face it, this guy is so good that if you don't use chansey, p2 should be considered on the team. It gives teams endgames without having to go semi-stall. It scouts, it sweeps, it walls... It is really fucking unique thanks to the bland typing and good bulk. Allows for great maneuverability on what you need done and gives a "wild card" as I discussed a while ago. A way out of bad situations, more than any other pokemon. Access to bolt beam, recovery and utility moves (I prefer magic coat over toxic right now for taunt/rock leads). This one is a great addition to any team lacking chansey/fighting weakness. One of two mons that can beat the devastating mixed mega chomp. Beats prankster thundurus, turns Greninja into a liability, and gives you nigh instant win vs teams with Gliscor. Underrated/overrated? Who gives a fuck, it's really good.
6. Heatran. I'm doing everyone a favor by having it here. It's EQ weak, fight weak, doesn't solve bisharp and loses a ton of momentum vs landorus versions. Really sucks vs Conkeldurr but Conk can't break Venu in a million years so who cares? Opens VenuTran cores up to be cracked easy by Lando-i, too. But, it takes Talonflame, most psychics and some ice/fire mons (whoops, you missed out on mamoswine, ZardYX and anything smart enough to have EQ, didn't you...)... So not most ice/fire types, eh? But what it does is set rocks, roar setup sweepers lacking EQ/fight moves and is a general pain for talonflame, the anti-venu. Any more, I'd prefer to fade this spot out for TFL's Krookodile, an Arcanine or maybe even Volcanion but for now he's it... And if you use ZardX, you lose venu-mega so... Well, it is decent but only due to Venusaur's success and heatran's synergy. On it's own, it'd be a decent stall mon but nothing more.
7. Chesnaught is one of my favorites in Gen6. Someone on Showdown (was it @IAmGingy?) told me to look into it when I started the triremes. I loved it and since have believed it is the second best mon xy gave stall this gen (sylveon wrecks lol). Edgequake resist, Venusaur mega deterrent (Venu needs Hp fire to get by I think), Gyarados/TTar-mega counter... Makes this guy so worth it. Great physical defense, special protect move, aegi counter, bisharp counter... Seeds on switch and deters opponent chansey/quagsire... This guy is just too good to never look at. Would be my fifth in a world where Venu-mega didn't exist (Venu gone, heatran gone). Could easily be 6th right now.
8. Quagsire is almost a necessary evil. ZardX check/counter Idk... Stops mega Scizor, stops mega TTar... Well, you get the idea. Lots of boosters fall to him, but Bisharp (his first counter) kinda likes Grass Knot. Can't stop special boosters at all and can occasionally get railed by surprise HP grass (did you know ZardX has like 130 SpA? HP Grass spam hits at the worst possible time and it is a thing now because Quag can be so hard to get around. So his effectiveness has gone down dramatically. Still a nice check to certain BP chains but by no means a stop.
9. Charizard-X. Yeah, it's insane. Burn Support, Roost, Electric weak to resist, Immune to EQ base form (which, you trade immune to weak for 4x rock to 2x rock weak) and one of like 2 pokemon (reshiram other?) immune to burns that resists scald... But... It doesn't counter ENOUGH to ever be a cornerstone like Venu. In a vacuum, it is top 3 or 4. However, this is not the case. It does have a fantastic counter to ZardY, but Chansey exists and ZardX can't take Lando-i. There are limits here, and they are real. The Rock weakness means even though it resists volt turn, it still takes massive amounts of damage to it. On teams that are centered to keep rocks away, you might consider him. However otherwise... VenuMega, AggronMega, or GyaradosMega all have great roles without that rock weakness.
10. Clefable is, quite frankly, the worst cleric I've ever seen. I've used it probably 200 matches in cleric role and then just decided that team would be balance and changed Clefable into a CM sweeper. In the CM unaware role, it is passable. However, the bulk again lets it down... It simply cannot beat pokemon like Venusaur, Scizor, Excadrill and many other common issues at any boost. Dragonite WP gives it a huge niche and time to do work (as MG is a possible ability so they kinda go for a DD anyways... Idk why you'd ever assume MG first but w/e).
As a cleric, 1/10. (10 being like Venusaur's importance to stall... the highest available but not objectively perfect). Absolute garbage, can barely get wishes to teammates. As a CM sweeper (aka a semi-stall role), I'd give it a 6.5 or 7. Can't really overlook it... but it is easily redundant with another fairy or even chansey in some cases (for some reason, so much pink just doesn't work).