Because the "you have less options" argument goes both ways: you have less options to deal with M-Mawile, but your opponent also has less options to support it. There is no such thing as a "self-sufficient" pokemon, no matter how you stretch it.
I don't agree with this at all. Largely the reasons for Mawile's success is the support it can get from either of the teams that it's found on. Consider for Steel you have Klefki that can set up screens and then Skarmory and Heatran to switch into either of it's weaknesses. You can repeat this for Fairy with Togekiss and Azumarill respectively. Even looking past team support, I'd argue that Mega Mawile is easily one of the most self sufficient pokemon in the metagame right now, needing little invitation to threaten either offensive or defensive pokemon. I'm just going to introduce quite an amazing calc here:
252 Atk Life Orb Arceus Extreme Speed vs. 4 HP / 252+ Def Eviolite Chansey: 212-251 (33 - 39%) -- 99.8% chance to 3HKO
252+ Atk Huge Power Mega Mawile Sucker Punch vs. 4 HP / 252+ Def Eviolite Chansey: 218-257 (33.9 - 40%) -- guaranteed 3HKO
Mega Maw's Sucker Punch hits harder than the standard Arceus Extreme Killer set. This means offensive checks need to be able to swallow a really strong Sucker Punch, and Dark coverage is really really good this gen. Defensive Pokemon are set up on and are then annihlated by the appropriate move, Venu gets crushed by +2 Iron Heads, Skarm gets bopped by Fire Fang, honestly outside of Physically Defensive Arcanine it's almost impossible to have a guaranteed safe switch in to this thing. The capability to be able to threaten both offense and bulky archetypes is really what makes Mawile so special, as it literally needs very little support provided you use it correctly thanks to it's great typing, decent bulk augmented by Intimidate and almost a fear factor I guess. Someone once said to me you just don't switch on a Mega Mawile and it struck me how true this is, you literally don't dare to switch for the fear it sets up a Swords Dance and goes to sweep your team.
I'm not entirely certain on the Mega Mawile issue, but right now, I don't think it should be banned. I main Bug (weak to Fire Fang), Psychic (weak to Sucker Punch), Flying, and Water (both teams
Articuno I said struggle with it) and I personally have never struggled to KO Mega Mawile. If I lose to a fairy team, Mega Mawile is not the problem--and I never actively created a Pokemon solely for dealing with it. Also, I believe it has many counters on most types that are brought along anyway, and still have the added bonus of countering M-Mawile.
Flying: Skarmory can take a +2 Play Rough and Whirlwind it away, or you could rack up residual damage by roost-stalling with Rocky Helmet. You just have to watch out for Fire Fang (+2 Fire Fang is guaranteed OHKO after Stealth Rock). Both Landos have a chance to KO with EQ/Earth Power respectively. Mega Char X/Y can also beat Mega Mawile with strong Fire STABs. Mega Gyarados has EQ. Thundy-I has Prankster T-Wave.
+2 252+ Atk Huge Power Mega Mawile Play Rough vs. 252 HP / 252+ Def Skarmory: 157-186 (47 - 55.6%) -- guaranteed 2HKO after Stealth Rock and Leftovers recovery so you can continue Roost stalling or just get rid of it for later, allowing you to bring in your own set up sweeper (Mega Gyarados/Char X) and then scare Mawile later on.
Water: a little more tricky, but you have Azumarill Aqua Jet and Greninja Shadow Sneak/HP Fire. Also:
176 Atk Swampert Earthquake vs. 132 HP / 0 Def Mega Mawile: 228-270 (83.2 - 98.5%) -- 31.3% chance to OHKO after Stealth Rock
Play Rough OHKOs back, though, but this lets you get in the range for a priority move from one of the two previously mentioned Pokemon, if it doesn't OHKO. 176 attack is my personal creation, it nabs the possible OHKO here and on a couple other Pokemon. (Guaranteed OHKO if the Mega Mawile decides to invest in speed/SpD rather than HP/Def.)
Psychic: WoW Gardevoir kills. Also, Mega Metagross EQ does damage (and is resistant to Play Rough/Iron Head, but Sukcer Punch hurts). If it is burned, paralyzed, or just doesn't Sucker Punch, Victini. Nuff said. (But fine, I will say it, V-Create OP.) I also use screens Espeon, so I can set up Reflect then use Psyshock until Espeon dies, bring in Mega Metagross and bye bye M-Mawile.
Bug: Volcarona. M-Mawile hates Volcarona, especially as by attacking, it can be burned. Other than that, Mega Pinsir's Quick Attack outspeeds Sucker Punch, so you can usually get two hits in before they realize they have to use Fire Fang/Play Rough/Iron Head. Also, Band Scizor Bullet Punch hits neutrally, but does some damage with Technician. (Does about 1/3.) Sash Galvantula is another thing I use (usually for Sticky Web, but if I see something dangerous in the opposing line up, I'll switch it out for later), allowing you to hit hard with Thunder (but needs spin support from Forretress/Armaldo which is easy to give). Thunder+Band Bullet Punch combo allows you to possibly KO Mega Mawile, even if it is already at +2.
Some other types that I don't use often also have counters to Mega Mawile (and could potentially struggle with it):
Ghost/Ice: Destiny Bond Froslass. RIP
Dark: WoW Sableye
Opposing Fairy teams: Azumarill/M-Mawile
Rock/Fighting: Band Terrakion EQ
252 Atk Choice Band Terrakion Earthquake vs. 132 HP / 0 Def Mega Mawile: 270-318 (98.5 - 116%) -- guaranteed OHKO after Stealth Rock
+2 252+ Atk Huge Power Mega Mawile Sucker Punch vs. 0 HP / 0 Def Terrakion: 179-211 (55.4 - 65.3%) -- guaranteed 2HKO
Grass: Non-Fire Fang is walled by stally Ferrothorn. Also: Mega Venusaur.
Also, it obviously can't go straight to +2, meaning it needs a turn to set up (and you can hit it hard or phaze it out then). There are many other set up Pokemon that can sweep weakened teams after a boost or 2 as well (
Mega Sableye/Mega Char X/Mega Gyarados/SD Bisharp, etc.).
TL; DR: I main Bug/Psychic/Flying/Water and have never really struggled with Mega Mawile, there are many counters to it that are on just about every team anyway. It needs a turn to set up a Swords Dance so you can hit it then, and it is not the only deadly late game set up Pokemon. I'm not totally convinced either way though, just thought I'd throw this out there for the sake of both sides having something, and show how I deal with it on types that could potentially struggle to handle Mega Mawile.
Skarm loses to very common Fire Fang variants, and needs Rocky Helmet to even threaten it. Whirlwinding is fine and all, but that's not really dealing with the problem is it? Lando-I gets destroyed by a +2 Sucker Punch, Lando-T has to be the defensive set to take on Mawile throughout the game, and anyway, both are at best offensive checks, neither would dare to switch in on a Mawile for fear of getting obliterated by a STAB move. Zard Y can't stand Sucker and really struggles to switch in after rocks which are fairly easy to get up on a Steel team. Zard X is a nice check, but can't switch in and is still taking >50% from Sucker if the offensive DD set.
Azumarill Aqua Jet and Greninja Shadow Sneak barely scratches Mawile, especially if it comes in on them and gets it's Intimidate off on them.
252+ Atk Choice Band Huge Power Azumarill Aqua Jet vs. 252 HP / 0 Def Mega Mawile: 99-117 (32.5 - 38.4%) -- 97.8% chance to 3HKO
0 Atk Life Orb Protean Greninja Shadow Sneak vs. 252 HP / 0 Def Mega Mawile: 44-55 (14.4 - 18%) -- possible 6HKO
Yeah that Swampert is ok for getting the KO off in certain situations, but taking that much out of it's bulk detracts from it's fundamental role of checking Electric attackers and a dedicated rocks setter. It's presence is literally causing you to run a sub-optimal set. Wisp Garde does get a burn off but then just dies to Iron Head and again, it's not even a check. If if Swords Dances you lose a poke right there. You would literally never switch it in. Mega Metagross is a nice check and a better switchin but you even concede it takes a ton from Sucker. Victini vs Mawile is always a situation where the Mawile user will Sucker Punch, obviously this can be worked around but Victini isn't even a check unless running Wisp which is rare, but in that case it becomes a good check. Paralysis doesn't help Tini at all here as Sucker is always it's best option. Having to use a screen user+a specific poke is overcentralising, and even then any smart Mawile user will realise what you're doing when they see Espeon and just proceed to set up to negate the effect of your screens.
Volcarona is a very good check, but again it struggles with Rocks but is one of the better one's you've brought up. 1v1 Mega Mawile vs Pinsir is one where the Mega Mawile should pretty much always Play Rough first turn, as even EQ doesn't KO, the Pinsir user is then forced into a corner if it used QA the first turn as it pretty much has to use an attack other than QA or switch out as its on the flipside of the mindgames. Even if it EQ'd first turn, it's still on the negative end of the mindgames, as it needs more predictions to go it's way. Scizor is a good check to non Fire Fang variants, but is set up fodder for one's that do carry it. Sashvantula is extremely dependant on rocks not being up, and is not a reliable check.
Froslass: I'm sorry no, when you're having to rely on D bonders to keep mons in check, you're actually arguing for a ban.
Sableye: Yeah will usually scare it out, but if a Mawile user really wants to, they'll just SD on the predicted Wisp and then you're no better off.
Azumarill: 1v1 Mawile wins every time. Play Rough+Sucker is a 2HKO on every viable set while Azu can only 2HKO with Banded Waterfall, meaning Mawile wins as it can Sucker safely on the second hit.
M-Mawile: yeah using the argument a mon can check itself really isn't an argument not to ban it. If anything that shows the overcentralisation it causes.
Terrakion: Yeah banded sets are a good check, but I haven't seen a Banded Terrakion used by a good ladderer in forever. Scarf is pretty much the way to go, and that set loses 1v1 against Mawile.
Ferrothorn: good answer to non-Fire Fang variants, however it can get worn down easily and isn't really doing that much back. Decent check though.
Mega Venusaur: loses to Iron Head variants unless it's running Sleep Powder or Hidden Power Fire, both of which are rare nowadays. Decent check though again.
The difference between the pokemon you listed compared to Mawile is that they can generally only threaten one playstyle, have common checks or struggle to set up. Mawile has none of these flaws as it can threaten bulky or offensive teams, any check has to be able to swallow a ridiculously strong Sucker Punch that has great neutral coverage and KOes p. much every offensive mon at +2, and last but not least has one of the single best typings in the game alongside decent bulk, particularly on the physical side.
I think for your arguments in future, you'd be wise to use these definitions of Counter, Check and Revenge Killer. They're by no means set in stone, but they give a general idea.
Counter: Can switch in under any likely conditions(Rocks being up, pokemon specific situations eg. Sun being up if you're talking about countering Zard Y) into any likely move and either KO the opposing Pokemon or force it out. It can do this time and time again throughout the game, thanks to either great bulk or reliable recovery.
Check: May not be able to directly switch in due to field conditions or coverage, but can switch into certain moves that the pokemon could use and then proceed to KO it or force it out. May also be a counter that just gets worn down too quickly to actually be called a counter, because it can't do it later on in the game.
Revenge Killer: Generally a pokemon that can't come in at all, but given a free switch can force the pokemon out or KO it.
These definitions aren't concrete and overlap in areas, but provide a rough framework with which to define your answers to a certain pokemon. If we use these definitions for Mawile, then the only things that can be listed under counter are generally Physically Bulky Fire types that aren't weak to Sucker Punch. Not only are these rare in themselves, they're generally quite limited in terms of what mono you can use them on.
Overall, I don't really see any concrete no ban arguments, this thing is ridiculous in the metagame and it's time has come.
