Probability in Warhammer Underworlds - Part 1 Attacking
Underworlds has its own unique dice, although they are still 6 sided (d6). So we can use some simple maths to work out the probability of a particular roll.
Attack Dice
The 'white' (they are different colours in different season, but in the starter box they are white) attack dice in Underworlds have 6 sides and 5 unique symbols. The Smash symbol, or 'hammer' is the symbol that appears on two sides of the die. All the other symbols only appear once.
With a single die attack and no support, the most accurate attack is with 'hammers'. So how do we calculate this success.
Let us consider all of the possible option with one die.
When a single die is rolled there is a 1/6 chance of any particular face being rolled.
So, there is a 1/6 chance (16.67%) of a Crit being rolled. There is also a 5/6 chance that Crit will not be rolled. This is really important for calculating the chance of success with multiple dice.
A 1/6 chance (16.67%) of a Fury 'Swords' being rolled.
There is a 2/6 chance (33%) of a Smash 'Hammer' being rolled because it appears twice on the die.
So to calculate success (with a single dice), we need to count the number of sides that would be successful and divide it by the number of faces on the die.
What is the chance a fighter with a single Smash attack with a single supporting fighter would successfully hit?
This fighter would therefore be successful if they rolled: Smash, Crits or Single Supports. In total, these symbol cover four of the six sides of the dice.
A single dice smash attack with a single supporting fighter would therefore have a 4/6 chance (66.67%) of success. The is also a 2/6 chance (33.33%) of failure.
In other words this fighter should hit two out of three times.
So who has a more accurate attack, a 2 dice Smash attack or a 3 dice Fury attack?
We will assume first of all that neither attack has any supports.
Bahannar. The 2 dice Smash attack.
As discussed, each attack dice has two Smash and a single Crit on it. Therefore, there are 3 chances for failure (3/6). Then there are two dice, so 3/6 x 3/6 = 9/36. The percentage for failure for this attack is (9/36) 25%. The chance of success is (27/36) 75%.
Each dice has one Sword and one Crit on its faces. Therefore, there are 4 chances for failure (4/6). Then there are three dice, so 4/6 x 4/6 x 4/6 = 64/216. The percentage for failure for this attack is (64/216) 29.6%. Therefore, the chance of success is (152/216) 70.4%
So initially, the hammer attack is slightly better. Now we have to take into account the chances of a critical hit.
Here we can see, that the critical hit percentage is better for three dice rather than two dice. Not really a surprise.
With these two attacks the chances of success are very similar, albeit slightly greater for the Smash. However, the increase chance of a Crit with the three dice Fury results in this attack being harder to stop. The three dice Fury attack is more likely to result in damage to the opponent.
Increasing the accuracy of attacks
Internal Surrender from the Tooth and Claw Rivals deck |
Some Warhammer Underworlds cards provide bonus dice to attacks. These in effect are increasing the accuracy of the fighters.
Bahannar (our 2 Smash fighter) has a 75% chance of success with his attack and a 30% chance of Critical success.
Slakeslash (our 3 Fury fighter) has a 70% chance of success with his attack and a 42% chance of a Critical success.
So how much more accurate, do they become with a bonus dice?
Bahannar
(3/6 x 3/6 x 3/6 =27/216 chance of failure, therefore 189/216 chance of success).
Has a 87.5% chance of success with a 42% chance of a Critical Success.
Slakeslash
(4/6 x 4/6 x 4/6 x 4/6 = 256/1296 chance of failure, therefore 1040/1296 chance of success)
Has a 80% chance of success with a 51% chance of a Critical success.
What happens to my accuracy if I lose attack dice?
Inviolate Prophet from the Paths of Prophecy Rivals deck |
Part 2 - Defence Probability can be read here.
Part 3 - Magic Probability can be read here.
Comments
Post a Comment