Altaria-Mega @ Altarianite
Ability: Pixilate
EVs: 248 HP / 84 Def / 176 Spe
Bold Nature
- Hyper Voice
- Fire Blast / Earthquake
- Roost
- Heal Bell / Earthquake
Role: Tank, Support
What It Does: The given speed EVs are to outspeed Adamant Bisharp so you can use Fire Blast before it can get an Iron Head off. If you have mons on your team that can handle Bisharp well, and you don't really have a problem with Bisharp, then you could run a bulkier Mega Altaria set and put all the Speed EVs into Defense. Also, if you are only running Earthquake as your coverage move, just switch Hyper Voice out for Frustration and give Mega Altaria a Bold Nature. Mega Altaria fits best on Bulky Offense teams because of its ability to switch in on a plethora of mons (second time I've said "plethora" this week), and dish out damage in return. Mega Altaria is also nice because it provides valuable Cleric support in Heal Bell, which can be a great help to Bulky Offense. Mega Altaria is able to switch in on a lot of things (I'm too lazy to list them all). But like mons such as Mega Venusaur or Mega Sableye, Mega Altaria likes to be able to switch into opposing mons healthy. Before you switch out Mega Altaria, try to keep it at a good amount of health so it can switch in again later in the battle.
Good Teammates: Mega Altaria does a pretty good job on Sand Offense (pretty much just Tyranitar and Excadrill). Since Mega Altaria can handle Lati@s, you don't really need a Scarf Pursuit trapping Tyranitar. This allows you to run Fire Blast on Tyranitar and it frees up Mega Altaria to run just Frustration and Earthquake (although Fire Blast is kind of nice on Mega Altaria). Since Mega Altaria has almost nothing for Stall, running a Stallbreaker on your team such as Gliscor, Mew, or Talonflame is usually a good idea. In my experience, Talonflame usually works the best as a Stallbreaker. Having a few solid Checks to Greninja is also a necessity on Mega Altaria teams. Good examples are Weavile, Conkeldurr, Tentacruel, Ferrothorn, Keldeo, or Rotom-W. Talonflame and Mega Charizard-X can set up for free on Mega Altaria so switch ins to those are a good idea. Sand Offense, Gliscor, Lando-T, and Rotom-w are some good mons to use.
What Counters It: Depending on the coverage moves you are running, certain Steel types will wall you. If you run Fire Blast over Earthquake, then Heatran will wall you. If you run Earthquake over Fire Blast, then mons like Skarmory and Ferrothorn will wall you. Like I said before, Stall is a big problem for Mega Altaria because it has nothing to touch Stall. Charizard X and Talonflame can set up on Mega Altaria with no worries. Also fast Ice type pokemon and Greninja can kill Mega Altaria (not Ice Shard because of its bulk), but they can't switch in on Mega Altaria. To be honest, anything that outspeeds Mega Altaria, or is bulky and can take a hit, and has a Super Effective moves can be problematic. This would include Gengar, Mega Gardevoir, Scarf Magnezone, Azumarill, Clefable, Sylveon, Slowbro, and Mega Venusaur
Additional Info: I'd recommend running this Mega Altaria set over the DD/Sub/Roost set because as long as your opponent has one Steel type healthy, you won't really be able to do anything with it. And since Steel types are so common in the meta right now, Mega Altaria has a hard time being able to sweep.