# Horde Fighting Cheat Sheet ### Target Numbers and Success Probability

| TN |Success |TN (ADV)|P (ADV)|TN (DIS)|P (DIS)| |:--:|:------:|:------:|:-----:|:------:|:-----:| | 20 | 0.05 | 19 | 0.10 | - | 0.003 | | 19 | 0.10 | 17 | 0.19 | - | 0.01 | | 18 | 0.15 | 15-16 | 0.28 | - | 0.02 | | 17 | 0.20 | 14 | 0.36 | 20 | 0.04 | | 16 | 0.25 | 12 | 0.44 | 20 | 0.06 | | 15 | 0.30 | 11 | 0.49 | 19 | 0.09 | | 14 | 0.35 | 9-10 | 0.58 | 19 | 0.12 | | 13 | 0.40 | 8 | 0.64 | 18 | 0.16 | | 12 | 0.45 | 7 | 0.70 | 17 | 0.20 | | 11 | 0.50 | 6 | 0.75 | 16 | 0.25 | | 10 | 0.55 | 5 | 0.80 | 15 | 0.30 | | 9 | 0.60 | 4 | 0.84 | 14 | 0.36 | | 8 | 0.65 | 3-4 | 0.88 | 13 | 0.42 | | 7 | 0.70 | 3 | 0.91 | 11 | 0.49 | | 6 | 0.75 | 2 | 0.94 | 10 | 0.56 | | 5 | 0.80 | 2 | 0.96 | 8 | 0.64 | | 4 | 0.85 | 1 | 0.98 | 7 | 0.72 | | 3 | 0.90 | 1 | 0.99 | 5 | 0.81 | | 2 | 0.95 | 1 | 0.998 | 3 | 0.90 | | 1 | 0.95 | 1 | 0.998 | 3 | 0.90 | - **TN** -- target number. - **Success** -- probability of success. - **TN (ADV/DIS)** -- adjusted target number for advantage or disadvantage correspondingly. - **P (ADV/DIS)** -- probability of success with advantage or disadvantage. ### How to Use the Table

#### Option A: Roll Dice for Each Enemy

This is best suitable for online play, as many virtual tabletops offer easy ways to roll multiple dice. For example, 10 goblins shoot their bows at rogue with Armor Class 16. With their +4 to hit they need to roll 12 or higher (0.45 or 45% chance of success) . So you can roll 10 dice and count successes. That also works for **saving throws.**

>##### How to Roll Ten Dice Using VTTs > For the goblins from above: > - **Fantasy Grounds:** "/roll 10d20s12" (without quotes) will roll 10 dice and count results of 12 and higher as success. > - **Roll20:** "/roll 10d20cs>12sd" will do the same for Roll20. ``` ``` #### Advantage and Disadvantage

If you roll a die per enemy it becomes problematic when advantage or disadvantage come into play. It would double the amount of dice and these dice had to be rolled in pairs. In order to deal with it you can use the **adjusted target numbers** from the table on the right. When our goblins have advantage, they only need to roll 7 or higher (see the row with their normal **TN** of 12) . If they have disadvantage, then the target number will be 17. With this adjustment you can roll one die per monster and have a statistically correct chance to succeed. If there are two values in a row, feel free to use any of them. I'd suggest using higher numbers for "weaker" monsters and lower numbers for stronger ones. Or just favor your players and always use the higher. #### Critical Hits

Rolling two dice when attacking with advantage means that 20 on any of them results in critical hit. Therefore the probability of crit becomes 0.098 which is pretty close to 0.1 or 10% . So when you roll a single die for a monster with **advantage**, it scores a **critical hit on a result of 19 or 20.** In case of attack with disadvantage, the probability of crit drops to 0.0025 which is negligible (at least when we talk about a horde of nameless grunts), hence if monsters of your horde have **disadvantage** they **never score critical hits.** #### Option B: Use the Average Probability

This is better for a faster play or if you feel that rolling 30 dice is too tedious. Let's use our running example with ten goblins. With their 45% chance to hit, that would mean 4 out of 10. Multiply that for their average damage, and voila! If they have advantage, their chances rise to 70% , now 7 out of 10 hits. With disadvantage it's only 20% , 2 out of 10. Fast and easy, but no crits and no outstandingly lucky rolls. ### Group Token Size

While VTTs can handle pretty large amounts of tokens, it might be helpful to merge a group of creatures into a single token on the battlemap. 5 -- 8 creatures take up space approximately as a creature of two sizes larger. 10 -- 15 creatures -- tree sizes larger. So 15 Small goblins would take one huge creature's space. Bigger groups are probably better to split into smaller ones. ### Damage and Area Effects

Allowing single target damage to carry over to other monsters of the group plays well with a fantasy of cleaving or piercing multiple foes. Number of monsters affected by AoE is roughly proportional to the affected area of the token. I use "all" - "half" - "one or two" granularity. ### Attacks of Opportunity

If a creature moves inside a threatened area of a horde, one monster from the horde gets an attack of opportunity per square of movement. If a creature moves out of the horde's reach, 3 monsters attack it.

Options