Omega-Xis
Mauville's Own
Just here to post about an element of the metagame that I find discussion worthy and that was very controversial in ORAS. When I say I find it discussion worthy, I'm not saying I want to jump right on a ban bandwagon. I would agree with people who say that with the influx of mons like the Tapus, some types now have access to or have access to more options to deal with Mega Sab. While I do find that statement valid to some extent, I also think that that's a reason not solidly grounded in the metagame.
Ground
In Gen 6, this felt like a much different matchup to me, and the main factor I can attribute that to is the burn nerf. M-Sab was very annoying to deal with as Ground if you weren't in the perfect mon to deal with it as it came out (and nobody was bringing their Sab in hard on a Lando-I) it would find something to easily CM on. This wasn't as annoying, however, due to the fact that Gastro could stomach hits for quite awhile, burn Mega Eye and cause it to lose 1/8 a turn. By the time you found an opportunity to switch it was usually chipped enough that you just soaked a burn on another special attacker or could use something like Mix MegaChomp or Exca to EQ it down if it was Mega'd.
More or less just wanted to comment that it feels even harder this gen to beat with less chip and it's much harder for ground if it gets to +1 than last gen. I really felt the need to be perfect to win, and I didn't get that feeling in ORAS using Ground against M-Sab.
Ghost
Ghost v Ghost seems just as gross as last gen (Who wins the CM war? Which +6 M-Sab crits?) I think enough people saw CM wars last gen to be sick of that song and dance. The addition of Mimikyu in my opinion adds an unhealthy element to this matchup in particular. With Jelli + Dou + M-Sab with Dhelmise/Gourg in the back soaking EQs, the matchup will be decided by who spreads more burn and who effectively uses Prankster/Magic Bounce to greater effect. To quote from the OU tiering policy's section on unhealthy elements being presented in a game:
"A.) These are elements that may not limit either team building or battling skill enough individually, but combine to cause an effect that is undesirable for the metagame.
1.) We haven't really had an example of an unhealthy ban yet, but a potential example is Stealth Rock; it certainly is on the mind of every team building experience and games are often steeped in Stealth Rock strategy."
The potential example in this case is Will-o-Wisp. Who spreads more burns wearing down Mimikyu and the core of Jelli + Dou + Dhelm/Gourg backing up M-Sab?
I would add Dragon and Fighting here as well but I'm still uncertain on whether or not I think Mimikyu is a potential bigger offender or if it's some other element altogether. I've just seen some Ghost vs. Dragon/Fighting games and M-Sab + Mimikyu seems very strong together in addition to the defensive sponge backing them up.
As I think you maybe have gotten a sense from my post, I find M-Sab a lot more threatening on Ghost than Dark, although as the policy goes if the community/council ever did have the discussion, a suspect was initialized and there was a vote, we as a community, would have to vote to ban it from both, and initially M-Sab on Ghost alone could possibly warrant that in my opinion. Mimikyu is an incredibly strong offensive addition to back up M-Sab and having this new offensive element of being able to take a hit for free essentially exacerbates the problems that M-Sab. Prankster burns to initially wear down offensive threats making it easier for the core of Jelli + Dou + Gourg/Dhelm/(ok Decuideye I'll put you here too I guess I know some people have a soft spot for you). After Mega, Magic Bounce and the combination of Mimikyu's ability make it incredibly difficult to ever wear down.
I will end this by saying, however, that I think there are far more imposing mons in the metagame. Not going to name any since I don't want to detract from the post, but I do think there are other things worth looking at. Any replays on this topic are more than welcome, I haven't saved any yet for games I've spectated or my own that I've played, still doing a lot of building, refining, etc. Also like I said, while I maybe have really sounded pro ban with this, all I wanted to get out there is that to some extent I have the same feeling that a lot of pro ban people had last gen and I think that as a community we have to definitely look at M-Sab at some point this gen and it needs to be on our list, even if it is down a bit in priority.