I'm hesitant about Mega Metagross as well. While there are a lot of fire types in this tier, none of them exactly love switching into Metagross. DarmanitanDLuffy is also right in that there aren't a ton of ghosts and grounds, who haven't been banned, who can handle Metagross. Gengar can speed tie it and has good attacking prowess but it's not very good otherwise in this tier, is frail and vulnerable to Bullet Punch.
But the real problem I can see with Mega Metagross is agility. This is where it goes from dominant to overwhelming in my eyes. After an agility, Mega Metagross outruns most of the meta game (no pun intended.) With just three moves in STAB steel coverage, either Meteor Mash or Bullet Punch, Earthquake and a choice for last move.
Thunder Punch for Gyarados, Charizard, Dondozo, Greninja, Alomomola, Corviknight and Tornadus among others
Ice Punch for Landorus, Dragonite, Zapdos and Gliscor
Knock Off for opposing psychics, ghosts and for neutral coverage against most things with the benefit for item removal.
Psychic Coverage like Psychic Fangs or Zen Headbutt to really hit Great Tusk, Mega-Lopunny, Zamazenta, Urshifu.
Stone Edge to really destroy Charizard and Moltres while retaining good damage on Tornadus, Zapdos and others.
Fighting coverage for the few darks in this tier that might survive a Meteor Mash + Ursaluna.
A lot of so called, checks, will die to a coverage option or at the very least be crippled since it's immune to toxic and with Bullet Punch not even Paralysis is safe. The best status to use is Burn but that is risky to pull off reliably since you hit will o wisp setters really hard, and again, Stone Edge smacks Moltres into oblivion while Knock Off removes its boots and thus makes it vulnerable to Stealth Rock.
The only thing I can see holding Mega Metagross from being outright broken is that it can't Tera, doesn't hold another item and only gets four moves. But the sheer power of this thing makes me very suspicious to say the least.
But the real problem I can see with Mega Metagross is agility. This is where it goes from dominant to overwhelming in my eyes. After an agility, Mega Metagross outruns most of the meta game (no pun intended.) With just three moves in STAB steel coverage, either Meteor Mash or Bullet Punch, Earthquake and a choice for last move.
Thunder Punch for Gyarados, Charizard, Dondozo, Greninja, Alomomola, Corviknight and Tornadus among others
Ice Punch for Landorus, Dragonite, Zapdos and Gliscor
Knock Off for opposing psychics, ghosts and for neutral coverage against most things with the benefit for item removal.
Psychic Coverage like Psychic Fangs or Zen Headbutt to really hit Great Tusk, Mega-Lopunny, Zamazenta, Urshifu.
Stone Edge to really destroy Charizard and Moltres while retaining good damage on Tornadus, Zapdos and others.
Fighting coverage for the few darks in this tier that might survive a Meteor Mash + Ursaluna.
A lot of so called, checks, will die to a coverage option or at the very least be crippled since it's immune to toxic and with Bullet Punch not even Paralysis is safe. The best status to use is Burn but that is risky to pull off reliably since you hit will o wisp setters really hard, and again, Stone Edge smacks Moltres into oblivion while Knock Off removes its boots and thus makes it vulnerable to Stealth Rock.
The only thing I can see holding Mega Metagross from being outright broken is that it can't Tera, doesn't hold another item and only gets four moves. But the sheer power of this thing makes me very suspicious to say the least.