1. What do we want our Mega Ability to accomplish? Should it be patching a weakness, enhancing a strength, and/or putting us in line with our Threats list?
We didn't patch a weakness before, we more enhanced the CAP's sustainability (a middle way if you will). But I think this time, enhancing the strength(s) of the typing is the best way to go, following the Threat List carefully (this shouldn't even be a separate goal, but the goal in and of itself). I also want to touch on something that has irritated me several times (in this thread alone even): threatening Water-types does NOT require hitting them super-effectively. Besides the fact that most Water-types take neutral or better damage from at least 1 of our STABs, there is also the unknown factor of WHAT the CAP's stats would look like. So it's too early to want to talk about hitting things super effectively.
Speaking of STABs, I think Adaptability is a pretty good ability to look at. It gives more leeway in the stats, meaning that we can still maintain the defensive capabilities of this CAP without hurting it offensively. As I've noted, our STABs also hit most Water-types (and several Psychic-types) at least neutrally, meaning that an Adaptability-boosted hit will surely sting them enough that they cannot carelessly switch in. This maximizes the efficiency of our decent neutral coverage, without doing much against the types we want to tank our hits (Steel and Ground). It's better than Sheer Force, in that it guarantees a boost to both of our STABs (rather than just Rock Slide and Ancient Power), and we can't know what coverage moves this CAP will have.
Sand Stream is still as good an option as before. It isn't so reliant on timing as it would have been as a base form ability, so there's a bonus in that regard. It becomes a great support/utility for certain teams just by switching in, and the boost to its Special Defense also gives more leeway in stats. Most everything has been said about this in the base form ability discussion and even in this discussion
Compound Eyes is certainly a notable ability, boosting the reliability of some of the STAB options (and some support options like Toxic possibly). This only matters if we are definitely going the physical route though, which is why it's not particularly a great option, nor a bad option.
Keeping Regenerator is an option too, and not a bad one. Great longevity is never a bad thing, and it maximizes the typings ability to check Fire and Flying types (along with making sure we can continue to check Weavile). At the same time, it covers the annoying problem of a Mega Pokemon lacking residual recovery (something the base form can choose to have). Finally, it guarantees that you will Mega Evolve as soon as possible.
Arena Trap is a very powerful ability, but worth a look. It won't let you trap Flying-types (or Ghost-types), so it's not a perfect way to trap the Pokemon you want to counter. But it does mean you control the flow of the battle by choosing what Pokemon you fight, a great advantage for a Pokemon with such a difficult typing to work with. Fire-types are basically screwed (except maybe Heatran) since even the Flying ones have to flee and let a teammate take a hit. It'll force many Fire-types to alter their movesets to make sure that they aren't too easily trapped either, so Arena Trap can easily backfire. Clefable will be in massive trouble, since it cannot escape and will have to take a Poison hit. The utility itself is actually pretty limited if you look at the Viability Rankings, as many of the top Pokemon are not ones you want to stay in against regardless, but the trap does put the play in your favor, since they cannot double switch. I think that last point is the main benefit of this ability, and quite a massive power in general.
I have to say, Unaware is a nice option for both enhancing strengths and reducing weaknesses. It doesn't actually make this CAP take on most set-up sweepers that well, as most of them hit super-effectively and it won't enjoy Scalds no matter what. But it provides a similar utility to Sand Stream, and an all-around better answer to M Charizard-X and Thunderus-I. Oddly, it also means Serperior and Volcarona are far less threatening. The CAP won't be overpowered by SD boosted M-Heracross and Breloom anymore either (Spore still sucks but w.e.). It the ability too good? Say that when you try switching this in against SD Scizor or Mega Metagross and you'll likely realize that it's still limited in what it can do.
Wasn't too huge a fan of Solid Rock before, and the possible increase in stats doesn't make it look any better, as the more specialized defensive abilities in Sand Stream and Regenerator have more of an impact. Rattled was an interesting option in the base form discussion, but it's too situational to rely on for the Mega form, and the +1 to Speed is a rather small benefit. It worked before because the base form would receive the boost, and then there was the option to Mega Evolve into a more potent ability that made use of a possible Speed boost. Alone, the Speed boost is just kind of mediocre (though it does depend on the stats and movepool as well). Sturdy is not really a good idea, Regenerator only heals you when you switch out after all. You still take hazard damage on switch-in, breaking your Sturdy. Relying on Defog or Rapid Spin support is not normally a problem, but you certainly can't rely on Mega Sableye or Mega Diancie support for Magic Bounce (for obvious reasons I hope). A lot of effort just to make sure the Sturdy stays intact though, when the CAP is supposed to provide utility itself. Rock Head is a bit presumptuous, since it steers us to Head Smash, and possibly other recoil moves. While anti- poll-jumping kind of fell out of the water early on in the process, an ability that only benefits 1 major possible move leaves a bad taste in my mouth.
In the previous thread, Natural Cure was brought up. Removing Burns and paralysis is a nice benefit, and Sleep and Freeze are a cute bonus. In the end, it may not be a strong enough ability to make people want to give up Regenerator, so I'd like to hear thoughts on this. Sand Rush and Sand Force were also noted before, though this CAP doesn't have Sand Stream as a base form ability. They do require additional teammates, but they boost the offensive capabilities of the CAP, meaning it can focus more on its defenses initially.
