>>15706264>in b4 lel shit casualSerious advice:
Gyro Ball is a good idea, but you might need to sacrifice Meteor Mash for it. Or Bullet Punch. There's no reason to have three Steel-type moves on him.
Hammer Arm + Gyro Ball is a good combination.
Zen Headbutt is a nice STAB move.
The problem is that if you run all three of the above and Bullet Punch, you lack coverage against Fire types. Personally I'd say Earthquake is a good move for him, but it won't hit Charizard Y - you could always ditch EQ and make sure you have a counter to commonly used Fire types (Volcarona, Charizard Y) like a Water type.
Also, be aware that Steel no longer resists Dark types. Hammer Arm should handle that, but it's best to be cautious.
So, personal opinion on moveset:
-Bullet Punch (getting that last hit in)
-Hammer Arm (gets rid of Dark types, helps max out Gyro ball)
-Gyro Ball (see above)
-Earthquake (takes out most Fire types, also hits Rock and Steel types)
Its EVs should ideally be focused around its attack and bulk. Since Metagross has no recovery, it's a bit silly to split EVs into HP/Def/SDefv since it still won't last long. I'd recommend:
252 Attack is a definite.
Split the rest between HP and Special Defense, e.g. 176 HP and 56 SDef. (Not those numbers exactly, it's just an example. Use Psypoke's stat calculator if you want to see what his stats would be at level 100 with each spread.) His Defense is high enough to take a few physical hits on its own.
Alternatively just stick 252 in HP, 252 in attack and the last 4 into special defense. It depends what you're going for.
Also, give it Quick Claw if you want to troll in online play. Alternatively you can try either Air Balloon to switch into Earthquake or Leftovers/Shell Bell if you want some recovery.