Just going to clear up a few things about nape. Probably my last post on the matter because theres not much else to say and I dont really want to get into an argument.
Infernape practically 6-0s most stall teams because you can 2HKO M-Venusaur/M-Sableye and if not mega evolved make it a bitch for it to come in, can take out Slowbro with Grass Knot reliably, beat Clefable, beats Amoonguss and the rest that Keldeo can also beat.
I can send replays if you want but I'm in a completely different country with just this phone so I'm hoping my past credibilities will make you guys at least look at this post.
156 SpA Life Orb Infernape Fire Blast vs. 252 HP / 144+ SpD Mega Sableye: 133-156 (43.7 - 51.3%) -- 5.9% chance to 2HKO
Factor in misses, pp staling courtesy of protect, and mega sableye constantly recovering on you, and nape is not very likely to be breaking this. As for venu, with rocks up it has a 14% chance to 2HKO which is admittedly more severe taking into consdieration the low PP of synth, but look at this:
0 SpA Mega Venusaur Sludge Bomb vs. 0 HP / 0- SpD Infernape: 169-201 (57.6 - 68.6%) -- guaranteed 2HKO
Nape isnt a good venu check at all honestly it needs good rolls two times in a row AND venu to try and switch into it with rocks up. Now im not going to sit here and say nape necessarially has a bad matchup against stall, but its not as good as you make it out to be. It certainly doesn't "practically 6-0" when you take this into consideration.
Not to mention Infernape has 2 solid boosting moves in Swords Dance and Nasty Plot as well as the same speed stat as Keldeo, and even access to priority moves on BOTH sides of the spectrum. This gives it a decent matchup against offense and balanced teams.
Infernape is honestly one of the most versatile Pokemon in the game and it deserves at least B-. Comparing it to Keldeo is somewhat silly.
Your logic doesnt quite follow here. You do say that it has two boosting moves and two priority moves, but you fail to explain
how this gives it a good matchup against balance/offense. Nape has pitiful bulk leaving it easily knocked out trying to set up against offensive teams and even if it does get the opportunity to set up it is easily stopped cold by any number of viable and common checks such as rotom-w, latios, thundurus, talonflame, tornadus-t, scarf lando, and much more. Balance is one of np/sd nape's better matchups but again, most balances are carrying something fast enough to revenge kill to avoid being steamrolled by manaphy. Versatility doesn't always equal viability if the mon is still not particularly effective at most of its jobs like mega altaria for example. And also, to be clear, in my comparisons to keldeo I was strictly talking about the defensive infernape set, which was what seth was advocating a rise based on in his first post.
Scald has 30% to burn while whisp has 85%. That's huge diffrence, no one can lie.
Infernape has diffrent typing (no grass and electric resist) and having reliable recovery is actually huge. Slack off heals 50% per turn while rest only 33% and you still have to relie on sleep talk. Moreover resttalk uses 2 slots whilr slack off only one. You can run taunt or stealth rock on extra slot.
Infernape has acces to stealth rocks.
Infernape can't get burn by sableye.
Of course I'm implying that Infernape is good enough for B-, not A+.
Scald also deals damage and just kills the grounds infernape has to predict to burn on the switch. Assuming we're still talking about defensive infernape, the grass resistance doesnt mean much of anything honestly. Youre not getting around anything like amoonguss anyways, serp just laughs at low kick and sets up on you, and breloom dies to secret sword from keldeo. Electrics will just volt switch on you and grab momentum regardless. Elecs that dont run volt switch like thundy can easily 2hko nape with tbolt while eating up its low kicks with ease. Running sr>taunt on defensive nape limits its ability to impair defensive cores at least somewhat effectively, as it gives even freer switchins to the likes of amoonguss or clefable. I personally prefer U-turn to either of those to grab momentum but maybe thats just me. Even if something like AoA infernape runs stealth rocks it has to give up valuble coverage meaning its going to be walled by clefable, waters, or heatran severely limiting its offensive potential. Defensive variants of infernape may not be burned by sableye but they cant hit sableye either leaving sableye free to knock off napes item, toxic nape, or even set up in the case of the rare calm mind variants.
I really don't think nape is better than lucario, zapdos, zygarde, victini or like anything else in C+, and I don't agree that its better than much of anything in B- like crawdaunt, hydra, or diggersby as a wallbreaker. As I've already said I don't really see a ton of value in defensive infernape when resttalk keldeo exists, its just so outclassed that defensive nape is a pretty niche option.
edit: keldeo gets taunt too fyi