Kyurem-Black @ Choice Scarf
Ability: Teravolt
EVs: 252 Atk / 4 SpA / 252 Spe
Naive Nature
- Ice Beam
- Outrage
- Fusion Bolt
- Earth Power

Dragonite @ Dragonium Z
Ability: Multiscale
EVs: 252 Atk / 4 Def / 252 Spe
Adamant Nature
- Outrage
- Extreme Speed
- Fire Punch
- Earthquake

Goodra (F) @ Assault Vest
Ability: Sap Sipper
Shiny: Yes
EVs: 248 HP / 252 Def / 8 SpA
Bold Nature
IVs: 0 Atk
- Ice Beam
- Focus Blast
- Sludge Bomb
- Fire Blast

Hydreigon (M) @ Focus Sash
Ability: Levitate
Shiny: Yes
EVs: 252 SpA / 4 SpD / 252 Spe
Modest Nature
IVs: 0 Atk
- Dark Pulse
- Earth Power
- Fire Blast
- Taunt

Garchomp @ Rocky Helmet
Ability: Rough Skin
Shiny: Yes
EVs: 252 HP / 200 Def / 56 Spe
Lax Nature
- Stealth Rock
- Earthquake
- Fire Blast
- Dragon Tail

*chara* (Latias) @ Leftovers
Ability: Levitate
Shiny: Yes
EVs: 252 HP / 252 Def / 4 SpA
Bold Nature
IVs: 0 Atk
- Calm Mind
- Psycho Shift
- Recover
- Stored Power

Hydreigon is used typically as a suicide lead that can either a) get powerful hits off a foe, or b) taunt mons that would otherwise set up hazards and whatnot. The sash is to guarantee at least one hit off a mon, and possibly get a kill (dark pulse drops Megagross to Dragonite's espeed range, Earth Power kills LO Tapu Koko, Fire blast for any ice/steel type that poses a threat to the team)

Kyurem-B is just a hard hitter; a standard fusion bolt, outrage, and ice beam set covers bulky flying types like Mantine, Celesteela and Zapdos, while outrage hits extremely hard at max attack (50% to physically defensive Chansey for instance.) Possible fourth moves for it can be iron head, hp fire, and earth power, but your choice depends on what you believe is a bigger threat.

Dragonite, another hard hitting mon carries Dragonium Z, which chunks other physically defensive walls such as Slowbro, Porygon2, Mega Sableye and Hippowdon, for at least 50-60%. Alternatively, Lum berry can be carried over dragonium Z for burns from bulky water types or other status from prankster mons like klefki.

Physically Defensive Goodra with AV is the weirdest part of the entire team, but It's bulk is unparalleled in the dragon mono. Sap Sipper can be used to prevent leech seeds from those such as Celesteela, and Max Def Bold nature lives many hits It normally wouldn't (i.e. M-Scizor Bug bite at +2) while still hitting solidly with a wide variety of coverage. Gooey also Is Viable to set up a position for Kyurem-B to Revenge Kill.

Garchomp is Standard Tank Chomp. It's the only rocker, and the only wall to mons like excadrill, which otherwise chunk everything else on the team.

Now Latias, my personal favorite mon on the squad, is CM Stored Power with the surprise option of Psycho Shift, which passes its Status onto the Opponent. CM ST Breaks Down Many Unaware mons like Clefable, Quagsire, and Pyukumuku, while also walling Magearna from Fleur Cannoning at +2 SpDef, and also lives Twinkle Tackle at full with about 11%. For this reason, It acts as a Setup Sweeper/Status Cleric, one of the only mons in the entire game that can really play that role at a high level. Substitute Can be used instead of Psycho Shift However for a wall to set up on.

TLDR:

Typically, you suicide Lead Hydreigon and use Garchomp for rocks. Everything Else has a level of bulk and can hit really hard, however this team has no defogger. Be very careful about how you wish to go about the situation. Typically 8 times out of 10, latias will be the wincon (unless vs. Dark or Steel.)