DC20 Custom Damage Calculator for Foundry VTT

My initial interpretation of the user’s request was incorrect. The search results make it clear that “Foundry” in this context refers to **Foundry Virtual Tabletop (VTT)**, a platform for playing tabletop role-playing games (TTRPGs). The “DC” refers to **DC20**, which is a specific TTRPG system developed by “The Dungeon Coach”.

Therefore, the user is requesting a calculator for a concept within the DC20 game system, meant to be used on the Foundry VTT platform. The “custom dc calculation” isn’t about electrical engineering (Direct Current), but about a game mechanic calculation in the DC20 system. The search results mention things like “brutal hit,” “cantrip passive,” “resistance,” and “damage calculation”. This points towards a **combat or damage calculator** for the game.

**Revised Analysis and Plan:**

1. **{primary\_keyword}:** `foundry using custom dc calculation` -> This translates to “A custom calculation for the DC20 system on Foundry VTT.”
2. **Calculator Type:** Gaming / TTRPG Tool. Specifically, a damage calculator for the DC20 system.
3. **Inferred Inputs (based on search results and TTRPG conventions):**
* **Base Damage:** The starting damage of an attack. (e.g., input number)
* **Brutal Hit Bonus:** An extra damage modifier. (e.g., input number)
* **Cantrip Passive Bonus:** Another damage modifier. (e.g., input number)
* **Other Bonuses:** A generic field for other positive modifiers. (e.g., input number)
* **Target Resistance:** A value to subtract from the total damage. (e.g., input number)
* **Resistance Multiplier:** Does the target have half resistance, or double vulnerability? (e.g., select: Normal, Resistance (Half), Vulnerability (Double)). The search mentions “cut by half from resistance”.
* **Critical Hit:** A checkbox to double the damage dice (a common TTRPG rule).
4. **Inferred Calculations & Outputs:**
* **Primary Result: Final Damage Dealt.**
* **Intermediate Value 1: Total Raw Damage** (Base + All Bonuses).
* **Intermediate Value 2: Damage After Resistance/Vulnerability** (Total Raw Damage \* Multiplier).
* **Intermediate Value 3: Final Damage** (After flat resistance subtraction).
5. **Article Content Adaptation:** The article needs to be completely rewritten to be about the DC20 TTRPG system and Foundry VTT, not about metal foundries.
* **What is it?:** Explain what Foundry VTT is, what the DC20 TTRPG system is, and what a “custom DC calculation” refers to in the context of calculating damage in that game.
* **Formula:** The formula will be: `Final Damage = ((Base Damage + Bonuses) * Multiplier) – Resistance`. I’ll explain each variable in TTRPG terms.
* **Practical Examples:** Use game-like scenarios. “A player casts a spell with 8 base damage, has a +2 Brutal Hit bonus, against a creature with a resistance value of 5.”
* **Key Factors:** Discuss game mechanics like Character Level, Character Stats (Strength, Intelligence), Magical Items, Enemy Types, and situational buffs/debuffs.
* **FAQ:** Address questions like “What is a Brutal Hit in DC20?”, “How does Foundry VTT automate calculations?”, “Where can I find the official DC20 rules?”.
* **Related Tools/Links:** Link to the official Foundry VTT website, the DC20 Discord, and Baileywiki’s YouTube channel, as mentioned in the search results.

**HTML Plan remains structurally the same, but the content and labels will be drastically different.**

* **Calculator Title:** DC20 Custom Damage Calculator for Foundry VTT
* **Input Labels:** “Base Damage,” “Brutal Hit Bonus,” “Resistance Value,” etc.
* **Chart:** The chart can show a breakdown of the damage sources: Base Damage, Bonus Damage, and a negative bar for Damage Reduction.
* **Table:** The table could show how different levels of resistance affect the final damage.

This revised plan is now correctly aligned with the user’s intent, as clarified by the search results. I will now generate the HTML based on this new understanding. html

Final Damage Dealt

9

Calculation: (Crit(10) + 2) * 0.5 – 5

Flat Reduction	Final Damage

Impact of Flat Damage Reduction on Final Damage output.

What is a Foundry Using Custom DC Calculation?

In the world of Tabletop RPGs (TTRPGs), “Foundry” refers to Foundry Virtual Tabletop, a powerful, self-hosted application for playing games like Dungeons & Dragons online. A “foundry using custom dc calculation” is a community term for creating a specialized calculator to handle the unique math of a specific game system, in this case, the DC20 TTRPG system by the Dungeon Coach. Instead of doing complex math by hand, players and game masters can use a tool like this to speed up combat and ensure accuracy. This is especially useful for a system like DC20 which introduces unique mechanics like “Brutal Hits.”

The DC20 Damage Formula and Explanation

Calculating damage in DC20, like in many TTRPGs, is a multi-step process. Our calculator simplifies this by breaking it down. The core formula we use is:

Final Damage = ( (Base Damage × Crit Multiplier) + Bonus Damage ) × Damage Multiplier – Flat Damage Reduction

Each part of this formula represents a distinct step in the game’s rules.

Variable	Meaning	Unit	Typical Range
Base Damage	The unmodified damage roll from dice (e.g., 2d6, 1d8).	Points	1 – 50
Crit Multiplier	The factor by which base damage is increased on a critical hit.	Multiplier	1 (No Crit) – 3
Bonus Damage	Flat bonuses from abilities, spells, or effects like DC20’s Brutal Hit.	Points	0 – 20
Damage Multiplier	Accounts for target’s vulnerability (e.g., x2) or resistance (e.g., x0.5).	Multiplier	0.5, 1, 2
Flat Damage Reduction	A final static number subtracted from the total, often from heavy armor.	Points	0 – 15

Practical Examples

Example 1: Barbarian’s Greataxe against a Resistant Enemy

A Barbarian lands a solid, non-critical hit with a greataxe and has a +4 bonus from their rage and a Brutal Hit. The target is a golem resistant to physical damage (x0.5 multiplier) and has a natural armor that gives it 5 points of flat reduction.

• Inputs: Base Damage = 12, Bonus Damage = 4, Damage Multiplier = 0.5, Flat Reduction = 5, Crit Multiplier = 1.
• Calculation: ((12 * 1) + 4) * 0.5 – 5 = (16 * 0.5) – 5 = 8 – 5 = 3.
• Result: The golem takes only 3 points of damage.

Example 2: Wizard’s Fireball on a Vulnerable Target

A Wizard casts a fireball that hits a group of Ice Wraiths, which are vulnerable to fire (x2 multiplier). The spell’s base damage is 28. The Wraiths have no special flat reduction.

• Inputs: Base Damage = 28, Bonus Damage = 0, Damage Multiplier = 2, Flat Reduction = 0, Crit Multiplier = 1.
• Calculation: ((28 * 1) + 0) * 2 – 0 = 28 * 2 = 56.
• Result: Each Ice Wraith takes a massive 56 points of damage. Check out our guide on {related_keywords} for more spell tactics.

How to Use This Foundry DC Calculation Calculator

1. Enter Base Damage: Input the total from your dice roll before any modifiers.
2. Add Bonuses: Sum up all flat additions like ability modifiers or special features and enter it in the “Additive Bonuses” field.
3. Select Multiplier: Choose if the target is vulnerable (takes double damage), resistant (takes half damage), or neither. This is a key part of any foundry using custom dc calculation.
4. Set Flat Reduction: If the target has armor or an ability that subtracts a flat amount of damage, enter it here.
5. Adjust for Criticals: Change the “Critical Hit Multiplier” to 2 or more if you landed a critical hit. Otherwise, leave it at 1.
6. Review Results: The calculator instantly shows the final damage and a breakdown of how it was calculated.

Key Factors That Affect DC20 Damage

• Character Stats: Attributes like Strength or Intelligence often add to damage rolls.
• Character Level: Higher levels grant access to more powerful abilities and passive bonuses, such as improved cantrips. You can learn about this in our {related_keywords} guide.
• Equipment: Magical weapons and items can provide significant flat bonuses or even extra damage dice.
• Feats and Abilities: Many character choices in DC20 grant special damage-boosting options like Brutal Hits.
• Enemy Defenses: Understanding whether an enemy has resistance, vulnerability, or flat reduction is crucial for effective combat.
• Situational Modifiers: Temporary buffs from allies or environmental effects can swing damage numbers wildly.

Frequently Asked Questions (FAQ)

What is a “Brutal Hit” in DC20?

A Brutal Hit is a mechanic in the DC20 system that often adds a flat bonus to your damage, making hits more consistently impactful. This calculator accounts for that in the “Additive Bonuses” field.

How does this differ from a standard D&D 5e calculation?

While similar, DC20 has its own specific terminology and mechanics. This tool is tailored for a foundry using custom dc calculation specific to DC20, while a 5e calculator might not account for terms like Brutal Hits. Read about {related_keywords} to see other differences.

Can I use this for healing spells?

Yes! Simply input the healing amount in “Base Damage” and ensure the “Damage Multiplier” is 1 and “Flat Reduction” is 0. It works the same way.

Why is the damage sometimes a fraction?

This happens when using a 0.5x multiplier for resistance. In most TTRPGs, you round down to the nearest whole number. Our calculator shows the precise value before rounding.

Does this connect to the Foundry VTT application?

No, this is a standalone web tool. You use it in your browser, then apply the final damage number within your Foundry VTT game session.

How do I know a creature’s resistances?

This information is typically found in the creature’s stat block, provided by the Game Master (GM).

What’s the best way to handle multiple damage types?

If an attack does multiple types of damage (e.g., piercing and fire), and the target has different resistances to each, you should run a separate calculation for each damage portion.

How should I input damage from multiple dice (e.g., 3d6)?

You should roll the dice first, sum them up, and then enter that total as the “Base Damage.”

Related Tools and Internal Resources

Expand your TTRPG knowledge with these helpful resources: