Is this metagross set viable in OU?
Metagross @ Weakness Policy
Ability: Clear Body
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Agility
- Meteor Mash
- Earthquake
- Thunder Punch
I wanna try it on screen team
I think Metagross is pretty unviable all things considered in the current meta game. It's main issue is power as it is really helpless against steels outside of banded coverage which can be exploited easily . It also struggles against the regen mons or general physical walls like Hippo and Mandi.
That being said if you are set on running it on screens then you can try cheese options like Cosmic Power Body Press but unfortunately it doesn't get Stored Power. I would suggest some block cheese strat if their weren't a million pivot mons in the tier. You can probably rob someone and get a sweep with the former set maybe in about 50 or so games but then again most probably not.
Another option I think you can enjoy is CB Explosion as it is disgustingly powerful and can lure some mons like -
252+ Atk Choice Band Metagross Explosion vs. 252 HP / 4 Def Slowking: 551-649 (139.8 - 164.7%) -- guaranteed OHKO
252+ Atk Choice Band Metagross Explosion vs. 252 HP / 200 Def Garchomp: 393-463 (93.5 - 110.2%) -- 62.5% chance to OHKO
252+ Atk Choice Band Metagross Explosion vs. 252 HP / 112+ Def Landorus-Therian: 405-477 (106 - 124.8%) -- guaranteed OHKO
252+ Atk Choice Band Metagross Explosion vs. 248 HP / 220 Def Zapdos: 416-490 (108.6 - 127.9%) -- guaranteed OHKO
It is still not as strong as you want it to be as Bro, Hippo, Tang, Mandi and all those other mons take around 70-90% it is still a lot but not an OHKO. You can check some threat like Lele, Kyurem, Rilla etc. with it's typing and great natural bulk. You can also use Bullet Punch to have some insurance. It can also prevent Defog while doing decent damage to Corvi-
252+ Atk Choice Band Metagross Explosion vs. 252 HP / 168+ Def Corviknight: 172-202 (43 - 50.5%) -- guaranteed 3HKO after Leftovers recovery
But don't get it twisted. What
Finchinator said is completely true. It is not viable and there are a whole lot better steel options like Bish. I solely wrote this considering that you were a fan and wanted to use it. It is not shockingly bad so you won't cripple yourself too bad by bringing it. I would personally suggest Banded Boom on Screens if you really want to use it and get some use out of it's bulk and latter sacrifice it as necessary and get Semi Reliable game to game use out of it.
But to your original Question, that set would struggle to beat defensive mons and is still kinda slow even at +2. I would firstly suggest to change to Jolly to outspeed Scarf Kart at +2. This type of set CAN sometimes work and sweep once in a blue moon . But it is the kind of set which you MAKE put in work, meaning it just is carried by your team and is GIVEN the kills or chances to sweep. It is not the kind of mon that can pull it's weight. It is not going to be a particularly great addition to your team. You would not miss it even if you remove it from the team.