SM OU New to competitive: first thoughts, in need of advice

[ArcanFlapper]

Introduction
Hello. As stated from the title, I'm fairly new to actual competitive battling. I've been reading about it here and there due to my interest in strategy games, and decided to finally give it a shot. I've designed my first actual team and tried it out already for a while. I feel like it's not really bad for a beginner, but still I feel like it needs some refining, so I would like some help.
As for the team itself, it's supposed to be a balanced team. In terms of weaknesses, I feel mostly they come from fire types (Talonflame, Charizard Y and Heatran for example) and Walls (Gastrodon and Chancey, for example).

Teambuilding Process
Worked around Reuniclus to begin. Was looking for a team that would resist hazard sets and also have good overall recovery and coverage.

The Team

Toxapex @ Black Sludge
Regenerator
252 HP/8 Def/248 SpD
Calm
- Recover
- Toxic Spikes
- Scald
- Haze

Works as a lead.
Recover, Black Sludge and Regenerator further expand survivability. Sets Toxic Spikes. Uses Haze on buffed sweepers. Scald is stab.
Usually works pretty well, however Toxic Spikes aren't always useful, so I wonder if I should keep it.

Gliscor @ Toxic Orb
Poison Heal
244 HP/152 SpD/112 Spe
Jolly
- Defog
- Knock Off
- Earthquake
- Roost

Mostly for support.
Roost, and the classic Toxic Orb Poison Heal for recovery. Defog for removing hazards. Earthquake is stab. Knock Off is coverage, but highly considering changing it.
Isn't always reliable in terms of speed, and the weakness to ice really hinders its potential, so I don't know if I should change its spread/movepool or find another hazard remover.

Kartana @ Choice Band
Beast Boost
4 HP/252 Atk/252 Spe
Jolly
- Leaf Blade
- Knock Off
- Smart Strike
- Sacred Sword

Glass cannon. Physical sweeper.
Leaf Blade and Smart Strike are stab. Knock Off and Sacred Sword are coverage. Choice Band for more damage.
Feels like an odd one for me. It does hit pretty hard, but I don't find it reliable in terms of speed, so I was considering if Choice Scarf or Focus Sash wouldn't be better options, or maybe finding another member to do its job.

Venusaur-M @ Venusaurite
Thick Fat
248 HP/88 Def/156 SpD/16 Spe
Calm
- Sludge Bomb
- Synthesis
- Hidden Power (Fire)
- Leech Seed

Tank.
Sludge Bomb is stab. HP Fire is coverage. Leech Seed and Synthesis are recovery.
Overall, feeling like I should change one of the recovery moves for Giga Drain for some Grass stab since there were times it was needed, but other than that it hasn't failed me.

Clefable @ Leftovers
Magic Guard
252 HP/252 Def/4 SpD
Bold
- Stealth Rock
- Soft-Boiled
- Moonblast
- Wish

Tank and support.
Sets Stealth Rock. Soft-Boiled for recovery. Wish for healing. Moonblast is stab.
Felt pretty solid to me, from what I could test.

Reuniclus @ Leftovers
Magic Guard
252 HP/212 Def/44 Spe
Bold
- Calm Mind
- Acid Armor
- Psychic
- Recover

Special Sweeper.
Calm Mind and Acid Armor helps set a great sweeper. Psychic for stab. Recover for survivability.
Very reliable, has been great for turning games in my favor.

Conclusion
I would greatly appreciate any in-sight or suggestion, and thanks for reading through.​

 

[Mawilover]

Hey there, i'm Mawilove!​

I missed your import. It's a bit annoying to have to copy Pokémon by Pokémon to put in the Teambuilder or whatever.
Looking at your team, I see a great lack of speed control, in fact i feel that you do not follow a structure for your team.

Threatlist -

After some tests, i saw that your team has problems against Psychic types, mainly: Tapu Lele and (Shadow Ball) Mega Alakazam.​

Mega Alakazam outspeeds your entire team, and OHKO or at least 2HKO all of them, same for Tapu Lele, but it (she?) can be revenge killed by Kartana. (This is even worst if you're against the Lele Zam core)

Major Changes​

Gliscor >

Landorus-Therian
Since your team was made to be resistant to Hazards, you do not need a dedicated Defogger. They are very similar pokémon in coverage, typing, and bulky, however, Landorus-T will bring to the table something you need: Damage, power, strength (As you yourself said, you are having problems with some walls). In order not to change your Pokémon, i thought i would just change the set to Swords Dance Gliscor, and you can do that if you want, but the difference in power and coverage is too great (Landorus-T 2HKOs the entire metagame lol), plus you have a vacant space for Z-Moves, soon, Landorus-T will fit perfectly. You also decide whether you want to use Flynium Z or Rockium Z. Flynium Z fits better, I think, because you get rid of Grass-types, that your team has certain problems, but Flynium Z is already so common that it can no longer be considered a lure. I particularly like the Rockium Z set, and Z-Continental Crush or +2 Earthquake is usually enough for the Grass-types.

Landorus-T

Landorus-Therian @ Flyinium Z
Ability: Intimidate
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Earthquake
- Fly
- Gravity
- Swords Dance

OR

Landorus-Therian @ Rockium Z
Ability: Intimidate
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Swords Dance
- Earthquake
- Stone Edge
- Rock Polish

Venusaur-Mega >

Tapu Bulu
You did not really give me a reason to use Mega Venusaur, and I think that Tapu Bulu will work much better on your team, having a greater overall synergy. Instead of staking out a weakness to Psychic, she holds them, avoiding the 2HKO of both Tapu Lele and Mega Alakazam, as well as removing Psychic Terrain to weaken their core, and as we speak on their terrain: It has a great synergy with their team, increasing the healing of Clefable and Reuniclus, which are pokémon hard to wear thanks to Magic Guard, and get even better with Grassy Terrain, in addition, the terrain greatly increases the power of your Kartana, especially that you need a late game cleaner, and its revenge kill power is absurd with active terrain; finally, the terrain decreases Earthquake's damage to Toxapex. Also Bulu has better offensive presence.

Tapu Bulu

Tapu Bulu @ Leftovers
Ability: Grassy Surge
EVs: 248 HP / 8 Def / 252 SpD
Careful Nature
- Swords Dance
- Horn Leech
- Superpower
- Synthesis

Minor Changes​

Choice Band >

Choice Scarf
Now that you already have a strong wallbreaker, you need what I mentioned earlier: Speed control. Scarf Kartana is the best for this, because its Base 109 Speed allows you to outspeedar many dangerous threats, including the Mega Alakazam, and OHKOing it. Do not worry about swapping the set for one with less damage, as Grassy Terrain's support will not leave you in the void, did you know that the Scarf Kartana Leaf Blade on Grassy Terrain is the same as the Leaf Blade of Choice Band Kartana out of Grassy Terrain? This is great, and in addition: Landorus-T will already be your wallbreaker, by the way, it works great with it, getting rid of Mega Scizor, Celesteela, Skarmory, and other things. Kartana will really Late Game Clean/Sweep after your mons (Mainly Landorus-T) have done their jobs, and you was in need of a Revenge Killer + Late Game Cleaner.
I thought about using Scarf Landorus-T and keep Kartana as your Wallbreaker, but Choice Band Kartana is a lot easier to deal with than Swords Dance Z-Crystal Landorus-T, and like I said, Grassy Terrain's support will give you damage enough.

Kartana

Kartana @ Choice Scarf
Ability: Beast Boost
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Leaf Blade
- Sacred Sword
- Smart Strike
- Knock Off

Toxic Spikes > Toxic
I'm not a Toxic Spikes fan on this metagame, and in your case it's even worse: You do not have sweepers who need and / or abuse Toxic Spikes (like SubZygarde or FakeOut Mega Lopunny), even you noticed that Toxic Spikes is not helping much, and was in doubt if it should keep, the answer is no.

Toxapex

Toxapex @ Black Sludge
Ability: Regenerator
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
- Scald
- Haze
- Recover
- Toxic

Wish > Thunder Wave / Knock Off / Flamethrower / Calm Mind
Why do you need Wish? Your entire team has no weaknesses to Hazards, has reliable recovery, and yet two of them have Regenerator, with Grassy Terrain, you'll get even more healing, I guess you do not need Wish. The options are in order of viability in this team, in my opinion. Thunder Wave is the best option to help 1v1 some boring and toxic Toxic pokémon, forming a good core with Toxapex to spread status conditions, and even helps with speed control, especially against Mega-Charizard-Y. Knock Off helps against many walls and is very good overall, especially against Steel-types like Celesteela, while Flamethrower is a direct damage way. Calm Mind I do not see need, but if you like it, it's acceptable.

Clefable

Clefable @ Leftovers
Ability: Magic Guard
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
- Moonblast
- Soft-Boiled
- Stealth Rock
- Thunder Wave

Final considerations​

Some other things you can use are Physically Defensive Toxapex, and Defog in Kartana or Landorus-T, instead of Knock Off and Rock Polish, respectively. You can also use Stealth Rock in the Landorus-T instead of Rock Polish to use Clefable with Calm Mind + Thunder Wave / Flamethrower, which is really something powerful, with a strong 1v1, but Clefable is a much safer rocker than Landorus-Therian .
It's also important that you know that you do not have to tell us what your Pokemon does, but rather because you put them there, we already know that Mega Venusaur is a tank, but we need to know why you chose it, for example, as I said , I chose Tapu Bulu to not change your team a lot, but hold the Psychic-types.
We have come to an end, these were my decisions, I suggest you test, and I believe you will like and feel difference, of course also that you do not have to follow all the changes (although it is recommended, and you have clear reasons for this), you can opt for some , although this will disrupt the purpose, have a good luck, and feel free to call me on Showdown.
Here's a example import of your new team:

Blessed from Mawilove

Messengelato (Toxapex) (M) @ Black Sludge
Ability: Regenerator
Shiny: Yes
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
IVs: 0 Atk
- Haze
- Toxic
- Scald
- Recover

Magileine (Tapu Bulu) @ Leftovers
Ability: Grassy Surge
EVs: 248 HP / 8 Def / 252 SpD
Careful Nature
- Swords Dance
- Superpower
- Horn Leech
- Synthesis

Hootcake (Kartana) @ Choice Scarf
Ability: Beast Boost
Shiny: Yes
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Sacred Sword
- Smart Strike
- Leaf Blade
- Knock Off

Anjelly (Clefable) (F) @ Leftovers
Ability: Magic Guard
Shiny: Yes
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
IVs: 0 Atk
- Moonblast
- Soft-Boiled
- Stealth Rock
- Thunder Wave

Cruiffsant (Landorus-Therian) @ Rockium Z
Ability: Intimidate
Shiny: Yes
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Swords Dance
- Earthquake
- Stone Edge
- Rock Polish

Buttlerusk (Reuniclus) (M) @ Leftovers
Ability: Magic Guard
Shiny: Yes
EVs: 252 HP / 212 Def / 44 Spe
Bold Nature
- Calm Mind
- Acid Armor
- Psychic
- Recover

- Mawilove, The Sweet Mawile
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