Doubles support (Gholdengo buddy)
Tinkaton @ Leftovers
Ability: Mold Breaker
Tera Type: Steel
EVs: 252 HP / 76 Def / 180 Spe or 252 HP / 76 SpD / 180 Spe
Jolly Nature
- Gigaton Hammer
- Protect
- Thunder Wave
- Helping Hand
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Mold Breaker allows Tinkaton to ignore Gholdengo's Good as Gold ability, paired with Helping Hand, this can help the pair dish out some serious damage. Thunder Wave will also work on on opposing Gholdengo, allowing for your Gholdengo to outspeed others.
With this EV spread + Jolly nature, Tinkaton should outspeed opposing Gholdengo (or Pokemon with base 84 speed or lower) that don't have the Choice Scarf or Tailwind or something. The remaining EVs would be put into bulk, and can easily be altered depending on the needs of the team.
Helping Hand Allows Tinkaton to buff teammates, Thunder Wave allows speed control (and can sometimes help in a pinch) Protect Incase something is threatening but you can't switch, and Gigaton Hammer because of Steel STAB that can deal decent damage if not resisted. Tera Steel to boost power of Gigaton Hammer, but you could also use Tera grass if you're worried about Spore/Sleep Powder, or even Tera Dragon to turn Fire weakness into resist, and Ground weakness to neutral.
As for teammates, in case it wasn't obvious, I recommend Gholdengo, but for other teammates I recommend Pelliper, because it has Tailwind and with Drizzle can get rid of Tinkaton and Gholdengo's Fire Weakness.