Mega Slowbro: A
Azumarill: Stay A+
Gengar: A+
Landorus-I: A+
MBro was a very hyped up 'mon, but you can't get past the fact it is prone to special attackers like Thundurus-I, Mega Manectric, Mega Gardevoir, Dark Pulse Greninja, Latios, etc making it hard to set up. Calm Mind + Iron Defense is completely match up based and useless against stall, since they will Toxic or Taunt you. CroBro is good, but you can't get past the fact that special attackers will fry it before you get a chance to sweep. Both sets can easily be phazed out, and is forced to use Slack Off repeatedly because of its low speed. Substitute Mega Gyarados can easily boost 'till the opponent's team is in oblivion, and considering it is one of the most dangerous threats atm, being set up bait for it sucks. Mega Slowbro can be really easy to wear down as well, and the importunity cost of losing Regenerator is a problem. If we are making a case for Mega Slowbro, it would be its all-out attacker set which hits ridiculously hard OHKOing the majority of Pokemon on HO teams with good prediction while maintaining good bulk to pivot in and out with. It can spread burns efficiently, and checks prominent threats using its great typing and bulk. Its other sets are really good, but I hate how they are match up based and need some threats removed before sweeping due to its aforementioned low speed.
Azumarill's Assault Vest got less effective in this metagame full of "passive damage", but two sets got much better. The decline of Ferrothorn and Amoonguss in the tier made the Choice Band set a lethal weapon. Against HO teams, your opponent is like forced to sack something. You can't just switch in to Choice Band Azumarill. Positive match-ups on all the new Megas is amazing like Mega Altaria, Mega Lopunny, Mega Gallade, Mega Diancie, and Mega Sharpedo. Belly Drum is just some kind of magic now that Knock Off + Aqua Jet + Belly Drum is legal. It usually sweeps through entire teams if left unattended, and you have more room to play with it. You can't abuse its good typing, but still a very potent set. The decline in Kyurem-B and some other checks makes Azumarill easy to fit on a team, and still worthy of A+ rank.
Gengar and Landorus-I have already been discussed - A+ worthy.
Azumarill: Stay A+
Gengar: A+
Landorus-I: A+
MBro was a very hyped up 'mon, but you can't get past the fact it is prone to special attackers like Thundurus-I, Mega Manectric, Mega Gardevoir, Dark Pulse Greninja, Latios, etc making it hard to set up. Calm Mind + Iron Defense is completely match up based and useless against stall, since they will Toxic or Taunt you. CroBro is good, but you can't get past the fact that special attackers will fry it before you get a chance to sweep. Both sets can easily be phazed out, and is forced to use Slack Off repeatedly because of its low speed. Substitute Mega Gyarados can easily boost 'till the opponent's team is in oblivion, and considering it is one of the most dangerous threats atm, being set up bait for it sucks. Mega Slowbro can be really easy to wear down as well, and the importunity cost of losing Regenerator is a problem. If we are making a case for Mega Slowbro, it would be its all-out attacker set which hits ridiculously hard OHKOing the majority of Pokemon on HO teams with good prediction while maintaining good bulk to pivot in and out with. It can spread burns efficiently, and checks prominent threats using its great typing and bulk. Its other sets are really good, but I hate how they are match up based and need some threats removed before sweeping due to its aforementioned low speed.
Azumarill's Assault Vest got less effective in this metagame full of "passive damage", but two sets got much better. The decline of Ferrothorn and Amoonguss in the tier made the Choice Band set a lethal weapon. Against HO teams, your opponent is like forced to sack something. You can't just switch in to Choice Band Azumarill. Positive match-ups on all the new Megas is amazing like Mega Altaria, Mega Lopunny, Mega Gallade, Mega Diancie, and Mega Sharpedo. Belly Drum is just some kind of magic now that Knock Off + Aqua Jet + Belly Drum is legal. It usually sweeps through entire teams if left unattended, and you have more room to play with it. You can't abuse its good typing, but still a very potent set. The decline in Kyurem-B and some other checks makes Azumarill easy to fit on a team, and still worthy of A+ rank.
Gengar and Landorus-I have already been discussed - A+ worthy.