I'm rather new, but I've lurked forever(or at least a couple months) so take this post with a grain of salt...
I feel as if Manaphy should be S rank for sure, given how quick it can set up and its relatively amazing match-up vs. balance and stall, and its incredible coverage options to catch some pokes which would usually check it off guard. That isn't to say it's a perfect poke or anything. But in my personal experience, it honestly is far and away one of the best wall breakers in the tier. I feel as if the people on the anti-S side of things are really looking over its capabilities. It may not be the strongest to start, and some things may be more powerful at +2 then Manaphy is at +3, but that isn't what makes Manaphy good. What makes Manaphy such a nice poke is it set up so quickly, gaining +6 in two turns, allowing it to reach its full power a lot quicker. Its this attribute that it possesses that makes it S rank in my eyes.
That isn't to say some of the anti-S arguments haven't made incredibly valid points(as well as a few pro-S arguments making a couple stupid/ irrelevant points imo). Manaphy is stupidly weak by wall breaker standards before it can set up. Other things are even stronger then it at +0 then it is at +3. And Manaphy certainly struggles against offense. But Manaphy has a great match-up vs. 2/3 of the main playstyles(relatively speaking of course). I feel that makes it S rank material.
Thanks for reading, and please don't ride me too hard if I messed up on something, as this is my first time ever posting on this thread.
Tbh, against a good player, you won't come to +6. And even if you get two boosts somehow I'm sure you would get two boosts in this match/against this player with any other wallbreaker, too. And if that's the one thing that is in your opinion the strength Manaphy has over other wallbreakers - I don't know.
Yeah, I know. Manaphy has other strengths too (that's why it's A+ after all) and we heard all the reasons a thousand times by now, but I just wanted to say something to this single point.
But nevertheless. Even boosting once isn't that easy (I'll explain what I mean later in this post). And that's the whole point about Manaphy, and the point for me why Manaphy is good A+ material, but not S: It's strong after one boost, and is has the bulk to boost once pretty safe, but that's not it. The thing is, what can Manaphy do after its boost?
Scenario (You with Manaphy against Balanced):
> Opponent has a Heatran and just KO'd one of your Pokémon
> Time for Manaphy, you're setting up TG
Scenario 1 (Offensive Scenario): Heatran switches out, Opponent switches in for example his Wallbreaker Specs Keldeo (even if you predict this, unboosted Energy Ball won't OHKO Keldeo) and -can- Secret Sword you. He don't need to, but he can, that's the point. He has the pressure on his side.
Scenario 2 (Offensive Scenario): Heatran switches out, Opponent switches in for example his Revengekiller Scarf Latios (even if you predict this, unboosted Ice Beam - You know the drill.) and -can- hurt you with Draco Meteor. If he didn't OHKO your Manaphy, you can kill him and he sacks in Latios, sure, but afterwards, you are nearly dead too and only managed to kill one of his Pokémon (and having a fast Pokémon like Latios or Keldeo or whatsoever in a team is so common, really really common. Nearly in every team, even Stall. But I'll say more about this point after the scenarios).
Scenario 3 (Defensive Scenario): Opponent sacks in his Heatran and does Earth Power before Heatran dies, switches in his Unaware Clefable and forces you to switch out. Or you're fishing for the burn and in the meantime Clefable wears you down with Moonblast (don't need much anymore after the Earth Power) or even CM+Soft-Boiled.
Yeah, these scenarios are very standard, cherrypicked and should be familiar with everyone, but that's not the point. The point is... - Their're even two main points.
1. Having one or two fast Pokémon isn't uncommon on Balanced Teams. Every HO and Balanced Team has offensive pressure, HO logically more than Balanced, but it's nevertheless there. Even Stall has most of the time one Pokémon which can act exactly like Keldeo or Latios in the examples. Plus, their're defensive Pokémon which can handle Manaphy too, like Unaware Clefable etc.
2. The lack of power before boosting is really the biggest point for me for Manaphy staying in A+. Manaphy -needs- to set-up, or it will be too weak for everything. And everytime Manaphy tries to set-up you lose momentum. The opponent has one turn more trying to handle your Manaphy, because even if you predict the right switch-in, uninvested you won't do much, and if you boost, Scenario 1,2,3,4,5,6,...can happen, because HO, BO, Balanced, and nowadays even Stall (it's not like they're unprepared) has solid answers to Manaphy, both offensive- and defensive-wise.
Their is a reason why a lot of people prefer hit-and-run wallbreakers nowadays like Specs Raikou/Sylveon/Keldeo/Latios, Banded Azu/Tyrantrum, M-Gardevoir, Charizard-Y, and so on. We use them, because of the immediate pressure against the opponent. You don't lose momentum, you don't give one free turn away, you just make a good amount of damage. And even if you don't, you still wear down the checks and counters.
However, a set-up wallbreaker isn't bad by any means, don't get me wrong. But for example SD Diggersby, SD M-Garchomp, SD Charizard-X, or Calm Mind Mega-Guardevoir: They don't -have- to set-up for their role as a wallbreaker. They -can-, and if they do - Holy moly. Manaphy however has no other choice. Manaphy -needs- to set up to fullfill its role, and this is the one single thing that makes it not S worthy for me. Manaphy has a lot of positive traits. All mentioned a dozen times in the last few pages. But the set-up argument kinda compensates it for me, and that's why
it should remain A+ IMO.
EDIT:
Plus, the whole point about Manaphy boosting so fast is kinda unvalid if you're considering that a lot of other wallbreakers are even stronger at +2 than Manaphy is at +3 (as stated in Srn's arguments). So the comparison between Manaphy and other set-up wallbreakers is pretty valid IMO.