Taking inspiration from WolfeyVGC's analysis on Regidrago, I decided to give it a go. The main attacker here will be Regidrago (duh).
Regidrago@Leftovers
Tera: Steel
Ability: Dragon's Maw
Nature: Modest (+SpA, -Atk)
EVS: 4 Hp, 160 Def, 252 SpA, 92 SpD
Dragon Energy
Protect
Earth Power
Tera Blast (Steel)
Okay, so I want Regidrago to be as healthy as possible for Dragon Energy so that's why it has leftovers. I made sure to heavily invest in its SpA to output the most damage. Protect to protect and to get more leftovers recovery. Earth Power for any steel types that resist dragon energy. Tera Blast steel to deal with fairy types. Tera Steel to deal with fairy types and steel types. Invested in Def and SpD to make it bulky.
Tornadus (M) @Leftovers
Tera: Grass
Ability: Prankster
Nature: Timid (+Spe, -Atk)
EVS: 48 HP, 196 Def, 128 SpD, 136 Spe
Tailwind
Icy Wind or Taunt (?)
Protect
Knock Off
Tornadus is a tailwind support for Regidrago cuz its slow. Tailwind. i cant choose between icy wind or taunt. I chose leftovers because i want tornadus to stay onfield alongside regidrago for as long as possible. protect for obvious reasons. knock off to get rid of other leftovers.
Ogerpon-Wellspring (F) @Wellspring Mask
Tera: Water
Ability: Water Absorb
Nature: Careful (+SpD, -SpA)
EVS: 4 HP, 252 Def, 252 SpD
Follow Me
Ivy Cudgel
Spiky Shield
Leech Seed
Honestly, I just needed Fire type coverage to get rid of other incineroars and ogerpons. maybe even torkoal. follow me to redirect damage cuz she is bulky (hopefully). ivy cudgel for stab. spiky shield because its better than protect. leech seed for passive recovery and chip damage.
Incineroar@Sitrus Berry
Tera: Fairy
Ability: Intimidate
Nature: Impish (+Def, -SpA)
EVS: 252 Def, 252 SpD, 4 Spe
Knock Off
Fake Out
Will-O-Wisp
Flare Blitz
i want it to be more bulky but also hits hard. knock off for leftovers and stab, fake out to get a free turn, will-o-wisp to cripple any physical attackers, flare blitz for stab and coverage against grass types.
Amoongus@Leftovers
Tera: Grass
Ability: Regenerator
Nature: Calm (+SpD, -Atk)
EVS: 252 HP, 252 Def, 4 SpD
Protect
Pollen Puff
Spore
Toxic
Protect for previously stated reasons, pollen puff to heal regidrago mostly, spore and toxic to either shut down buffed pokemon or to get rid of stall pokemon. tera grass cuz i dont plan on using tera on it.
Rillaboom@Assault Vest
Tera: Dragon
Ability: Grassy Surge
Nature: Careful (+SpD, -SpA)
Grassy Glide
U-Turn
Earthquake
Fake Out
Grassy Glide for stab, u turn to pivot, earthquake for fire coverage, fake out for a free turn. Rillaboom will be more of a late game sweeper once regidrago has fainted.
feel free to replace any pokemon except for regidrago. also, i really need help with evs and ivs. thank you so much :)