The Spinning Boulder Druid build revolves around manipulating core skills and utilizing companions to amplify your damage output significantly. With the right setup, you can achieve hits ranging from 200,000 to 400,000, and possibly even higher.

Build Planner:

Weapons and Armor
Helmet: Vil’s Prayer
Chest Piece: Insatiable Fury
Gloves: Metamorphic Stone (Place the Boulders core skill here)
Pants: Tibault’s Will
Boots: Symbiotic
Weapon: Shepherd’s Aspect (Ensure core skills deal an additional 20% damage for each active Ally or companion)
Amulet: Dolman Stone
Rings: Stampede and Retaliation

Skill and Stat Priorities
On the gloves, focus on Attack Speed, Critical Strike Chance, and Lucky Hit Chance.
For the boots, prioritize Movement Speed, All Stats, Willpower, and other useful stats.
On the weapon, aim for Damage to Crowd Controlled, Critical Strike Damage, Core Damage, Vulnerable Damage, Willpower, and All Stats.
For the rings, look for Critical Strike Chance, Lucky Hit Chance, Maximum Life, Damage to Crowd Controlled Enemies, and Critical Strike Damage.

Companions and Abilities
Utilize a total of nine companions – four Ravens, three Wolves, and two Poison Creepers. This will give you a 180% multiplicative damage boost from your two-hander, thanks to the core skills modification and the active companions.

Vampire Abilities
Prey on the Weak
Feed the Coven
Blood Boil
Sanguin Brace
Feel free to swap out abilities based on your preferences and the situation at hand.

Gems and Paragon Boards
Armor: Ruby
Weapon: Emerald
Accessories: Diamond (or Skull if resistances are maxed)
For Paragon Boards, focus on Weariness, Scythe Talons, Aven Wrath, Energize, and Calm Before the Storm.

Gameplay Strategy
The main strategy revolves around utilizing your Boulders core skill effectively while keeping your companions active. Ensure bosses are always poisoned thanks to your Poison Creeper, and be mindful of your skill rotations to maximize damage output.

Advanced Tips
Pay attention to your resistances, and adjust your gems accordingly.
Make use of the skill tree and Paragon Boards to fine-tune your build for optimal performance.

Conclusion and Additional Resources
This build provides a unique and powerful way to tackle the challenges of Diablo 4, offering immense damage output when set up correctly.