SM OU First team, any help?

[GibeMayona]

So I just built up a team but I wasn't sure if I was missing anything, is there anything I could do to make this team better?
The team basically centers around constantly gaining attack to easily ko the opponents mons.

Kartana @ Choice Scarf
Ability: Beast Boost
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Knock Off
- Sacred Sword
- Leaf Blade
- Return
So for Kartana, I usually use this mon late game for when my opponents mons are not at max hp so I can lower their stats and sweep the rest of their mons. The only issue with this is that it can get killed early game quite easily. I play only damaging attacks on him bc I feel like I wont really need to do any more stat changes since I have Beast Boost and Scarf on him so I already gain quite a lot of attack off those.

Tapu Koko @ Aguav Berry
Ability: Electric Surge
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- U-turn
- Brave Bird
- Reflect
- Light Screen
I play Koko early game to set up Light Screen and Reflect then U-Turn out to one of my attackers. I play Reflect and Light Screen on Koko because since its quite fast I dont really have to worry about getting hit first very often so I can set up at least one of the two before Koko dies. I also play Brave Bird on Koko because I dont really have any attacks to deal with grass types like Kartana, and I feel I can afford the recoil it deals.

Garchomp @ Choice Band
Ability: Rough Skin
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Earthquake
- Outrage
- Return
- Shadow Claw
I play Garchomp as another attacker since it has a really high base attack stat, but its quite slow. I play Band on Garchomp so I can outspeed more mons and deal some more damage. Again, I play only damage dealing attacks so I dont really have to worry about being stuck using a stat changing attack. I also play Shadow Claw on Garchomp as I dont have much Psychic coverage other than U-turn.

Jirachi @ Rocky Helmet
Ability: Serene Grace
Shiny: Yes
EVs: 252 HP / 4 SpD / 252 Spe
Timid Nature
- Stealth Rock
- U-turn
- Protect
- Moonblast
I play Jirachi as she can be really fast and can set up Stealth Rock very early and U-turn into an attacker. I play Rocky Helmet because Jirachi's base defense isnt that good and extra recoil is nice. I play Moonblast on Jirachi because I dont have any other Dragon or Fighting coverage and because it can lower the opponents Sp Attack which is helpful considering my mons dont deal well with special attacks.

Swampert-Mega @ Swampertite
Ability: Torrent
EVs: 252 HP / 252 Atk / 4 SpD
Adamant Nature
- Power-Up Punch
- Stealth Rock
- Waterfall
- Scald
I play M-Swampert as a tank as well as a main attacker because M-Swampert is quite bulky, especially with Light Screen and Reflect up. I play Stealth Rock on Swampert in case Jirachi is slower than the opponents mon so that I can set up Rock again. I play Scald on M-Swampert so that I have a chance to deal some extra damage to my opponents with burn damage.

Magearna @ Leftovers
Ability: Soul-Heart
EVs: 252 HP / 252 SpA / 4 Spe
Mild Nature
- Flash Cannon
- Brick Break
- Volt Switch
- Hidden Power [Poison]
I play Magearna as some extra Fairy coverage as well as another quick beatstick, hopping in and out with Volt Switch. I play Magearna as more of a special attacker because most of my other mons are based around their high physical attack stats, so Magearna is used to deal with the mons with low sp defense. I also play Brick Break to deal with my opponents Reflects and Light Screens so I can deal more damage with my physical attackers.

 

[TPP]

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[DrPumpkinz]

Kartana looks decent. I'd replace Return with Smart Strike, as it's slightly stronger thanks to STAB, and deals more damage to Fairy types. Your description makes it sound like you want Kartana's item to boost its power. Did you mean to give it a Choice Band?

I'd consider replacing Aguav Berry on Koko with Light Clay for more Screens turns. I'd also replace Brave Bird with Taunt to prevent the opponent from Defogging away your Screens, or Roost to keep Koko healthy throughout the match. You don't really need Brave Bird due to some other changes I'll make.

Garchomp's Earthquake actually hits Psychics harder than Shadow Claw, thanks to its higher base power and STAB, and Return isn't needed once again. I'd replace them with Dragon Claw for a Dragon STAB that doesn't prevent you from switching, and Stone Edge or Fire Fang to hit Flying or Steel types. Also, as with Kartana, you seem to be mixing up Choice Band and Choice Scarf. Scarf increases your speed, while Band increases your power.

Rocky Helmet's damage isn't like Counter, where it's proportional to how much damage you take, so your reasoning for putting it on Jirachi seems shaky (also 100/100 is great physical defense, what are you talking about?). I'd consider replacing it with Leftovers, to make more use of Protect. If you decide to keep Rocky Helmet, then replace Protect with something like Iron Head, Body Slam, or Secret Power, for flinches or paralysis. Moonblast actually seems like some neat tech, so if it's working, go on ahead.

Swampert has no business being on a non-rain team. You also don't have a Z-move user, and Screens works really well with set-up sweepers, so give this a shot:

Manaphy @ Waterium Z
Ability: Hydration
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Rain Dance
- Tail Glow
- Surf
- Psychic / Ice Beam

This Manaphy set has two Z-move options. Z Rain Dance boosts your speed, allowing you to plow through offensive teams. If the extra speed isn't needed, then you can use Hydro Vortex to crush defensive teams. Psychic hits Toxapex and Mega Venusaur harder, while Ice Beam hits Tangrowth and Tapu Bulu harder.

I doubt Screens are popular enough to warrant running Brick Break on Magearna, so I'd replace it with Fleur Cannon so you actually have the Fairy coverage you mention in Magearna's description. I'd also replace Hidden Power Poison with Hidden Power Fire. Hidden Power Poison pretty much only hits Tapu Bulu, who is already hit by Flash Cannon for about the same damage. Hidden Power Fire hits more Grass types, like Ferrothorn and Kartana, as well as hitting Mega Scizor. Finally, since you aren't running a physical attack anymore, run a Modest nature with 0 Attack IVs.

 

[ImBetterAtDigimon]

OK, first off switch return for smart strike to deal with Mons like flying types since they resist grass and smart strike with stab is a 105 bp move. Second off if you want to deal with grass types like kartanas (use taunt instead) but I would use hp fire to hit ferro hard also and ohko kartana and I would switch aguav berry for light clay for extra screen turns. 3rd garchomps set is out of control bad...to put it bluntly, out rage and eq is fine but ghost are not big in ou and outrage is 180bp to Shadow claws meager 140bp against ghosts and instead of Shadow claws and return run fire fang and stone edge or poison jab for hitting flying types and poison jab for fairies and grass types which aren't 4x weak to fire, and after that we have jirachi, the set is mostly fine and the only thing I don't get is having double rocks. And now we have swampert, power up punch is horrible on swampert, and no earthquake?! And with no rain settyer swampert is probably going to do horribly. BUT WAIT...MAGEARNA WITH HP POISON?! What kind of meme is this, first off HP poison is almost never better than flash cannon and use fluer cannon not brick break because screens are not popular, And instead of HP poison used ice beam a
Or aura sphere in my opinion. AND GUESS WHAT, NO DEFOG OR RAPID SPINNN are you friends with mr pebbles and his spiky friends? But other than All that your team could probably peak 1000 if you work hard and make plays. But honestly, ask me for any help with a team if you need any help team building or you want a team I'm your man.