To counter Gholdengo in Pokemon Scarlet and Violet, you can use the following Pokemon:

• Arcanine
• Hydreigon with Fire Tera-Type
• Baxcalibur with Fire Tera-Type

Arcanine

• Moves
  • Flare Blitz
  • Will-O-Wisp
  • Helping Hand
  • Sunny Day
• EVs*
  • HP – 150
  • Attack – 160
  • Sp. Def. – 200
• Nature
  • Adamant
• Ability
  • Intimidate
• Tera Type
  • Fire
• Hold Item
  • Sitrus Berry

*If you need additional information on how EVs work, here is a comprehensible guy on how to do EV Training in Pokemon Scarlet and Violet.

Strategy

• This Gholdengo counter strategy aims to one-hit KO this Pokemon using Fire Blitz.
• Even if Gholdengo has a fully EV-boosted HP and Sp. Atk., and has the Choice Specs held item, this build can resist a direct hit of Power Gem. However, if Gholdengo lands a critical hit with Power Gem, it will one-hit KO Arcanine.
• As well, Arcanine can survive the recoil of Fire Blitz thanks to the Sitrus Berry held item.
• With the EVs described in this build, Arcanine should be able to defeat Gholdengo with a single use of Fire Blitz unless Gholdengo has any boosted stats or a field effect like Rain is currently ongoing.
• Combined with Helping Hand and Sunny Day, this build is also great for Tera Raids, just like the one-hit KO Slowbro Nasty Plot build.

Hydreigon

• Moves
  • Heat Wave
  • Tailwind
  • Dark Pulse
  • Draco Meteor
• EVs
  • Sp. Atk. – 252
  • Sp. Def. – 180
  • Speed – 78
• Nature
  • Timid
• Ability
  • Levitate
• Tera Type
  • Fire
• Hold Item
  • Life Orb
• Level
  • 100

Gholdengo Counter Strategy

• This Hydreigon counter strategy depends entirely on Terastalization with a Fire Tera-Type. Once Terastallized, you can one-hit KO Gholdengo with Heat Wave.
• One of the first few instances in which this build might fail is if Gholdengo’s Speed is boosted by Tailwind (or other means), and it lands a Power Gem attack while holding the Choice Specs. In this case, you will survive the hit but faint after using Heat Wave due to the Life’s Orb 10% HP deduction. This is a rare occurrence, so you would be fine in most instances.

Baxcalibur

• Moves
  • Tera Blast
  • Icicle Crash
  • Dragon Claw
  • Snowscape
• EVs
  • HP – 62
  • Attack – 196
  • Sp. Def. – 252
• Nature
  • Adamant
• Ability
  • Thermal Exchange
• Tera Type
  • Fire
• Hold Item
  • Leftovers
• Level
  • 100

Strategy

• This Gholdengo counter strategy also requires Terastallization. Once Baxcalibur Terastallizes into a Fire Tera-Type, it can one-hit KO Gholdengo with the EVs described above.

Gholdengo Weaknesses

Gholdengo is weak to Fire, Ground, Ghost, and Dark attacks due to its Steel / Ghost type combination. This dual type also grants this Pokemon immunity to Normal, Fighting, and Poison attacks.

Understanding this chart will make countering Gholdengo a much easier task.

If you’re interested in getting your own Gholdengo, here is how you can get the 999 coins required to evolve Gimmighoul!