I think the possibility of exploring a monotype that does not currently exist in OU (or at least not in that specific role i.e. make a defensive monoelectric that would not be competing with Jolteon in any way) gives us an opportunity to learn what it takes to make it in OU when pokemon of that monotype, sometimes with great stats, movepool, or ability have not become OU.
We already know what it takes to make an offensive Pokemon OU. Mainly, being more effective than a similar Pokemon. Mismagius is not OU because Gengar is faster, stronger, has a better movepool and can do other things than prat about with weak Shadow Balls or try to set up. Mismagius has Nasty Plot - that makes not a blind bit of difference, because Gengar has the more sustainable niche. If Mismagius and Gengar had their stats and movepools swapped, their places in the usage stats would swap also. Similarly, Vaporeon is OU and Milotic is not because of Wish, which gives it a niche Milotic does not have. Making a mono-type attacker only constitutes making something that is stronger than something already in OU - and that's something we already know.
A bit of an extreme example, obviously, since no one would honestly make the case Eelektross belongs in OU... but why not? It has no weaknesses, great mixed attacking stats and not terrible bulk. True its speed is atrocious, but then, so are lots of mixed attackers.
Given that I wrote that analysis, I feel obliged to say: Eelektross is terrible. Everything in OU, pretty much, hits hard and fast, and while Eelektross can do impressive stuff like surviving Haxorus's Mould Breaker Earthquake, it cannot really hit anything hard enough to make it usable over, well, anything else. Its mixed attacking stats are not great. It languishes in the lower tiers because it is simply not as good overall, not for lack of a Fire-typing or whatever.
I think this path is much more interesting than taking two offensive types that cover each others' weaknesses and making another offensive threat. I'm looking to make something that will actually help us study the underlying necessities to be successful in OU. Not just: OK so we made an Ice/Fire Special Sweeper (with mountaineer or Magic Guard or whatever of course since CAP has a fetish with not being SR weak) with 110+ Special Attack and access to any move it needs to KO everything in OU that doesn't resist both STABS/is named Chansey/Blissey.
Yes, I would agree with you here. That would be a waste of time. Though as far as I can tell, nobody has suggested actually doing that, so I'm not sure what the point is here...
What if during the typing stages, we completely reverse the normal goal -- meaning let's make the goal to come up with "bad typing". Ignore everything else, just make it a contest to identify the worst typing combinations imaginable. Then after that, we revert and try to use every other step to overcome the bad typing. I think the typing steps would actually be very interesting. We would have some very good discussions on what constitutes "bad typing". And then later we specifically learn what things overcome bad typing.
The thing is that "the worst" typing in an OU context generally boils down to either being entry hazard weak (such as Ice/Fire) or priority weak (such as Ice/Rock). There are plenty of "bad" typings that don't come close to being as bad as these two categories. While this would be a legitimate way to go, perhaps, it does have the problem of greatly limiting our field of play, as there are typings that do happen to be legitimately worse than everything else and also nigh-on unsalvageable, save for extreme methods.
Point blank, the reason I'm paring it down to Mono-types and 2CTD is because both of these will force the Pokemon to use its STAB. 2CTD requires using both to maximize effective SE coverage and ward off threats, while mono-types will be built to use STAB. That is the only way I will consider the project a success, is that the end product must use a STAB attack on everything but perhaps some non-attacking stall set, if it somehow gets to that. That is a very high bar to set, but I believe it best fulfills the concept.
That seems like a ridiculously low bar to set, if anything. There is very very little in existence in BW that can actually afford to not use its STAB, and those that can are usually hyper-defensive Pokemon like Blissey and Dusclops - and if we manage to make a successful hyper-defensive CAP with a poor defensive typing, we will almost certainly have succeeded anyway. I imagine you have mono-Poison in mind when saying this - unless we are giving our Pokemon perfect three-move base 120 power coverage moves outside of Poison-type moves in addition to base 150 attacking stats and a number of boosting moves, it is extraordinarily unlikely that it would ever be able to lose the great neutral coverage afforded by its STAB.
To repeat a #cap example, take mono-Psychic. It has many of the same problems for an attacking Pokemon as mono-Poison, namely being more or less useless against Steel-types and Tyranitar. And yet Reuniclus, Alakazam, and Espeon all seem to do perfectly well using their Psychic-type STAB on attacking sets. So I don't think STAB is any great concern here.
I'd like to comment on this. What really is the worst type in the current state of OU? I'd argue that, despite the ubiquity of Steels, it's quite possibly mono-fire.
It's weak to SR, affected by Spikes, is crushed by both Rain and Sand teams. Resisted by Dragons. And because it's monotyped, it has no secondary STAB to deal with these things. Just like Volcarona would be useless against Sand with no STAB Bug Buzz to kill Tyranitar and Sp. Def Heatran wouldn't exist with no Steel-type.
Darmanitan was OU once. Victini, its closest dual-typed comparison, never came close.
Yes, mono-Fire isn't the best type, certainly. But it also certainly isn't the worst type in OU. It doesn't exist in OU at present because there are so many better things you could be using - Heatran and Infernape aren't weak to Stealth Rock, which is a great deal, and Volcarona has absurd advantages to its use even so, with high stats, Quiver Dance, and Fiery Dance, such that its dreadful typing is almost irrelevant defensively - it is, after all, a Fire-type that can more or less set up on bulky Water-types. If there were a mono-Fire-type with advantages that exceeded these, then yes, we would see it in OU. No such Pokemon exists. The best of them is probably Arcanine, which is admittedly very strong, but its stats are nowhere near sufficient to make it a usable bulky Fire-type over say, Heatran, who occupies a singularly better niche.
It's hard to truly make a dual-type be as bad as a monotype since the secondary STAB is almost always useful, even if it also adds defensive liabilities. The only secondary STABs that don't help ever pretty much offensively are Poison, Steel (bar Scizor or Metagross with their gigantic attack stat), and Normal.
You can't say that unless our CAP has some absurd set of offensive stats that making typing completely irrelevant, at which point you might as well be comparing it to Mewtwo or Deoxys-A, both of whom are, funnily enough, mono-Psychic. I suppose Volcarona is another comparison which could be made, and it would never be OU if it didn't have Quiver Dance or very high stats. It could, however, without its Bug-typing. Defensive ability will almost always come into it - see Pokemon like the previously mentioned Victini or even Moltres. Their secondary typings bring their own share of advantages and disadvantages. For a hyper offensive Pokemon these are not so bad. For a defensive or even a balanced Pokemon, these can be disastrous. Most mono-types are nowhere even close to as bad as the worst dual-types - although admittedly, the best are nowhere near as close to the best dual-types. They occupy the middle of the spectrum, as it were.
I say it again: Just because a typing is uncommon does not make it bad. There is a real tendency in this thread to simply examine the typing and totally ignore the Pokemon itself - Volcarona has a terrible, terrible typing, mostly because of Stealth Rock, but it is saved by its incredible offensive options and stats, which enable it to boost bulk at the same time as Speed and attacking power. Ask anybody before BW whether Bug/Fire was a bad typing and they would have said, "well duh". Now that Volcarona exists, this is no longer the prevailing view. Similarly, simply due to the lack of usable mono-types in OU, people seem to be using this as evidence that mono-types must be worse by definition. It only means that there are no mono-types with a viable niche, not that they are inherently bad. In Ubers more than a third are mono-types. More than half if you count all of Arceus's formes as different Pokemon. It means nothing.
The problem with any sort of mixed typing is that it is likely to lend itself to one of two scenarios: A) the second typing balances or checks the first typing's weaknesses well enough that the overall typing combined isn't exactly "bad"; or B) the typing combination is truly "bad", and forces the use of exaggerated abilities, stats, and movepool to make the Pokemon in any way viable.
I fail to see how either of these is a bad thing. We want the typing to provide some sort of advantage, not just to "be there", and even if the second is the case, it gives us a challenge to go forward with - trying to find ways to make it usable without going to extreme lengths. At least, without trying to patch up a typing that isn't necessarily bad to begin with, like mono-Fire, Poison, or Bug.
Pretty much agree with all of this barring the necessity of Wonder Guard. There are very few typings that would, I think, legitimately require Wonder Guard in order to be effective. I'd much rather try to be cleverer with stats and abilities together than solve the whole problem with a ridiculously good ability. Volcarona managed it - not very elegantly, true - but it still managed it.
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I will restate this again - I think we are going the wrong way about trying to decide what we want out of our Pokemon. I honestly believe that rather than trying to make x random type extraordinarily powerful by repeatedly lumping on various random benefits to make it stronger, such that it simply displaces something else currently in OU, we should try to focus it on a particular
niche - something that it can do that other Pokemon can't, simply by virtue of its typing alongside abilities or whatnot, or alternatively, something that it can do better than already existing Pokemon. This could take the form of countering very specific threats, or alternatively, a general playstyle.
For example, take BW Celebi. It doesn't have a particularly good offensive or defensive typing, and yet it is ideal, alongside its stats, for combating - as well as being a part of - the three big playstyles of BW, Sand, Rain, and Volt-turn. This is, granted, also achieved through a big BST, but then again, none of its individual stats are actually extortionate, unless you care to count 100/100/100 as unreasonable for a bulky attacker, as opposed to a wall. Another example of this is DPP Tyranitar. Rock/Dark isn't the best defensive typing, and doesn't give it particularly good resistances, but the combination of Sand Stream and its Rock typing enables it to take special attacks pretty damn well, and its Dark typing enables it to take out fast-but-frail attackers, like Starmie, Gengar, and before they were banned, Lati@s, as well as giving it a niche as the bulky, powerful Pursuit user.
So, I would actually like to see us try to create something that can take on a specific portion of the metagame well. A Fire/Rock with Dry Skin could make a pretty good Rain counter, as well as any other general utility it might have. An Ice/Steel with Snow Warning might make a reasonably good general weather counter, or alternatively a Grass/Rock with Cloud Nine. On the other hand, if we wanted a general counter to Terrakion, Gliscor, and Landorus, we could have a sort of Ground/Psychic Claydol v2, for sake of argument.
Even if this is not our primary focus, it is something we ought to be keeping in mind when choosing a typing. Unless, of course, we are picking a mono-type, in which case we'll just go all out with the movepool and ability anyway.