Hi there RMT! I'm not new to competitive Pokemon, but despite that I'm not great at building my own teams (or battling for that matter). Because of that I don't really know much of the more in depth terminology, so I am sorry if the title isn't right and if I get any roles of my mons wrong. Anyways my team is built around wearing down the opponent enough for either Dragonite or Dragapult to clean up. I can get to around 1450 on a good day but after that I start to plateau. Any help is appreciated!
goat (Ting-Lu) @ Leftovers
Ability: Vessel of Ruin
Tera Type: Fairy
EVs: 248 HP / 8 Atk / 252 SpD
Careful Nature
- Whirlwind
- Spikes
- Earthquake
- Protect
Ting-Lu is my mixed wall. I normally lead with it (or Dragapult) to threaten chip damage, set up hazards, or scout out how my opponent plays. Later in the game I use him more as a switch in to anything I don't want my other two dedicated walls. I run spikes over rocks because I find that most things, besides banded/orb Chien-Pao, that are weak to rocks wear boots, so I'd rather get the consistent damage off on Pokemon like Gholdengo, Iron Valiant, and Great Tusks for example. Also I noticed my team was susceptible to set up sweepers so I use Whirlwind over something like ruination or rocks. The hazard chip from WW is nice too. Tera Fairy is just to get rid of weaknesses while maintaining a good defensive type that doesn't overlap with anything else on my team.
washing machine (Rotom-Wash) @ Leftovers
Ability: Levitate
Tera Type: Electric
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
IVs: 0 Atk / 30 Spe
- Volt Switch
- Hydro Pump
- Protect
- Will-O-Wisp
Rotom-W is my physical wall. I run Wisp over T-Wave because with Extreme Speed D-nite and Dragapult I wasn't having a problem with speed control, and every thing else on my team is so slow that T-wave didn't really help. I run max defense because banded Chien-Pao really threatens my team, in fact Chien-Pao is another reason I run Wisp over T-Wave. Protect is used over Thunderbolt because the passive recovery and ability to scout is nice. 30 Speed IV's is to under run other defensive Rotom-W.
mushroom (Amoonguss) @ Black Sludge
Ability: Regenerator
Tera Type: Poison
EVs: 252 HP / 128 Def / 84 SpD / 44 Spe
Bold Nature
IVs: 0 Atk
- Giga Drain
- Sludge Bomb
- Foul Play
- Spore
Amoongus is my special wall. It pairs nicely with Rotom-W and Ting-Lu because it covers several of their weaknesses. The three of them allows me to minimize the impact of misplays/bad luck. Amoongus's set is the one listed on the battle dex, so I don't know why it why it runs the EVs it does. I did take the liberty to take 44 EVs from its defense and put them in to speed to outpace base 35s like Dondozo and Garganacl as well win what would otherwise be speed ties with Slowking and opposing Amoongus. I like Black Sludge over Rocky Helmet because I find the ability to heal stealth rock damage nice on my team with little ways to clear hazards. In addition it hurts scarf trick Pokemon more than a scarf hurts me
metal elephant (Iron Treads) @ Assault Vest
Ability: Quark Drive
Tera Type: Water
EVs: 252 HP / 4 SpD / 252 Spe
Jolly Nature
- Rapid Spin
- Iron Head
- Knock Off
- Volt Switch
Iron Treads is my hazard remover/secondary pivot. I run Iron Treads over Great Tusk because of its steel typing, better speed, and access to a pivot move. Assault Vest is for me to switch/pivot from Rotom or Dragapult into Gholdengo, opposing special Dragapult, and, from full HP, an Aura Sphere from Iron Valiant. Iron Head is used over Earthquake as my team is weak to fairies, like mystical fire Hatterene, and Knock Off is enough to handle Gholdengo.
dragon (Dragonite) @ Heavy-Duty Boots
Ability: Multiscale
Tera Type: Normal
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Dragon Dance
- Extreme Speed
- Earthquake
- Fire Punch
Dragonite is one of my clean up mons. With extreme speed it can revenge kill things and then switch out. I try my best not to keep Dragonite out on the field unless I know I can safely set up with one or two Dragon Dances. I run Fire Punch over Ice Spinner because Corvinite, balloon Gholdengo, and Scizor are problematic for Dnite and other members of my team can take on other Pokemon that Ice Spinner would threaten, though because I do have Fire Punch I could replace EQ with Ice Spinner if needed.
ghost dragon (Dragapult) @ Choice Specs
Ability: Infiltrator
Tera Type: Fairy
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Draco Meteor
- Shadow Ball
- Flamethrower
- U-turn
Finally, Dragapult is my other clean up mon. Unlike Dragonite, I don't mind letting it take a bit of damage if it means I can potentally stay in on the field or come in on resisted hit and KO something. In addition it hits on the special side so it forms a nice physical/special synergy with Dragonite. There isn't much else to say, most of the time I click Draco Meteor or U-Turn and then go into one of my walls.
PROBLEMS:
These are things that even I noticed so it must be pretty bad
Volcarona
Tera Grass Volcarona are very annoying for me, almost always requiring me to bring out Dragonite and DDing on it to kill with Espeed as it does too much to everything else.
Garganacl
Probably my #1 threat. Salt Cure does too much to Rotom so I can't Hydro Pump and threaten it without taking 60% or more of my HP, and Amoongus can't KO Garg before Amoongus takes too much salt cure damage and is forced to switch.
Hatterene
Despite putting Iron Treads on the team, I still have trouble with this mon just being fat and doing large chunks to my team as I have no way to resist all of her moves at once.
Kingambit
Neither of my clean up dragons can take this on well and only really Rotom-W and Ting-Lu can challenge it. Endgames where Rotom and/or Ting-Lu have been worn down and KG is the last mon on their teams are very hard to deal with.
Here's the pasta:
https://pokepast.es/d4d27a7f826d0b97
Thank you for looking at my team!
goat (Ting-Lu) @ Leftovers
Ability: Vessel of Ruin
Tera Type: Fairy
EVs: 248 HP / 8 Atk / 252 SpD
Careful Nature
- Whirlwind
- Spikes
- Earthquake
- Protect
Ting-Lu is my mixed wall. I normally lead with it (or Dragapult) to threaten chip damage, set up hazards, or scout out how my opponent plays. Later in the game I use him more as a switch in to anything I don't want my other two dedicated walls. I run spikes over rocks because I find that most things, besides banded/orb Chien-Pao, that are weak to rocks wear boots, so I'd rather get the consistent damage off on Pokemon like Gholdengo, Iron Valiant, and Great Tusks for example. Also I noticed my team was susceptible to set up sweepers so I use Whirlwind over something like ruination or rocks. The hazard chip from WW is nice too. Tera Fairy is just to get rid of weaknesses while maintaining a good defensive type that doesn't overlap with anything else on my team.
washing machine (Rotom-Wash) @ Leftovers
Ability: Levitate
Tera Type: Electric
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
IVs: 0 Atk / 30 Spe
- Volt Switch
- Hydro Pump
- Protect
- Will-O-Wisp
Rotom-W is my physical wall. I run Wisp over T-Wave because with Extreme Speed D-nite and Dragapult I wasn't having a problem with speed control, and every thing else on my team is so slow that T-wave didn't really help. I run max defense because banded Chien-Pao really threatens my team, in fact Chien-Pao is another reason I run Wisp over T-Wave. Protect is used over Thunderbolt because the passive recovery and ability to scout is nice. 30 Speed IV's is to under run other defensive Rotom-W.
mushroom (Amoonguss) @ Black Sludge
Ability: Regenerator
Tera Type: Poison
EVs: 252 HP / 128 Def / 84 SpD / 44 Spe
Bold Nature
IVs: 0 Atk
- Giga Drain
- Sludge Bomb
- Foul Play
- Spore
Amoongus is my special wall. It pairs nicely with Rotom-W and Ting-Lu because it covers several of their weaknesses. The three of them allows me to minimize the impact of misplays/bad luck. Amoongus's set is the one listed on the battle dex, so I don't know why it why it runs the EVs it does. I did take the liberty to take 44 EVs from its defense and put them in to speed to outpace base 35s like Dondozo and Garganacl as well win what would otherwise be speed ties with Slowking and opposing Amoongus. I like Black Sludge over Rocky Helmet because I find the ability to heal stealth rock damage nice on my team with little ways to clear hazards. In addition it hurts scarf trick Pokemon more than a scarf hurts me
metal elephant (Iron Treads) @ Assault Vest
Ability: Quark Drive
Tera Type: Water
EVs: 252 HP / 4 SpD / 252 Spe
Jolly Nature
- Rapid Spin
- Iron Head
- Knock Off
- Volt Switch
Iron Treads is my hazard remover/secondary pivot. I run Iron Treads over Great Tusk because of its steel typing, better speed, and access to a pivot move. Assault Vest is for me to switch/pivot from Rotom or Dragapult into Gholdengo, opposing special Dragapult, and, from full HP, an Aura Sphere from Iron Valiant. Iron Head is used over Earthquake as my team is weak to fairies, like mystical fire Hatterene, and Knock Off is enough to handle Gholdengo.
dragon (Dragonite) @ Heavy-Duty Boots
Ability: Multiscale
Tera Type: Normal
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Dragon Dance
- Extreme Speed
- Earthquake
- Fire Punch
Dragonite is one of my clean up mons. With extreme speed it can revenge kill things and then switch out. I try my best not to keep Dragonite out on the field unless I know I can safely set up with one or two Dragon Dances. I run Fire Punch over Ice Spinner because Corvinite, balloon Gholdengo, and Scizor are problematic for Dnite and other members of my team can take on other Pokemon that Ice Spinner would threaten, though because I do have Fire Punch I could replace EQ with Ice Spinner if needed.
ghost dragon (Dragapult) @ Choice Specs
Ability: Infiltrator
Tera Type: Fairy
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Draco Meteor
- Shadow Ball
- Flamethrower
- U-turn
Finally, Dragapult is my other clean up mon. Unlike Dragonite, I don't mind letting it take a bit of damage if it means I can potentally stay in on the field or come in on resisted hit and KO something. In addition it hits on the special side so it forms a nice physical/special synergy with Dragonite. There isn't much else to say, most of the time I click Draco Meteor or U-Turn and then go into one of my walls.
PROBLEMS:
These are things that even I noticed so it must be pretty bad
Volcarona
Tera Grass Volcarona are very annoying for me, almost always requiring me to bring out Dragonite and DDing on it to kill with Espeed as it does too much to everything else.
Garganacl
Probably my #1 threat. Salt Cure does too much to Rotom so I can't Hydro Pump and threaten it without taking 60% or more of my HP, and Amoongus can't KO Garg before Amoongus takes too much salt cure damage and is forced to switch.
Hatterene
Despite putting Iron Treads on the team, I still have trouble with this mon just being fat and doing large chunks to my team as I have no way to resist all of her moves at once.
Kingambit
Neither of my clean up dragons can take this on well and only really Rotom-W and Ting-Lu can challenge it. Endgames where Rotom and/or Ting-Lu have been worn down and KG is the last mon on their teams are very hard to deal with.
Here's the pasta:
https://pokepast.es/d4d27a7f826d0b97
Thank you for looking at my team!
-> 
my only pokemon change is changing rotom-wash to dondozo. firstly 
changing dragonite from fire punch to roost will be of great benefit to this team. volcarona is really only an issue when dragonite breaks its multiscale, and since you are basically forced into it to take a hit from volcarona, it isn't hard to break that multiscale. so, roost will be much more 
changing amoonguss to 
changing iron treads to sr/eq/spin/knock will prove to be much more useful for this team. your main breaker, dragapult, has a great defensive typing means it does not need volt switches to come in, especially off fatter teams. the defensive core of tinglu/amoong/dozo also works very well in ensuring that you can play defensively and make doubles off of them as well. stealth rocks is very important for this team as it did not previously have a rocker, and eq > iron head is very much preferred as the only real ground resists in the tier are abused by dragapult.