Editing System grab-bags:Dice-based (section)

==Critical Events==

If a certain number, or range of numbers, is rolled special events occur. The most common is the critical success or critical failure. In these events the task automatically succeeds or fails, generally in a somewhat spectacular fashion, regardless of any other considerations. 

Examples: On a D100 roll, 1-5 are critical successes and 95-100 critical failures. On a 2D6 roll, two ones is a critical failure, with two sixes being a critical success.

===Botch dice===

If the ”failure number” is rolled, the failure is not automatic. Instead, a variable number of dice are rolled - the worse the circumstances, the more dice. If any of them turns up the ”failure number”, the task fails. The more failure numbers, the worse the failure.

Example: On an attribute + D10 roll, the player rolls a 0, indicating a possible failure. The circumstances give her three botch dice, so she rolls three D10s, which come up (4, 3, 0), confirming the critical failure (though only a mild one).
Game examples: Ars Magica

===Confirm the critical===

The success or failure is not automatic on rolling a certain number. The critical must be confirmed by making another roll: if that would have been an ordinary success, the roll was a critical.

Example: On an attack bonus + D20 roll, the player rolls a 19, indicating a possible critical. He rolls again, a 13, which combined with his attack bonus is enough to hit the enemy. This elevates the attack roll into a critical, dealing extra damage.

Game examples: Dungeons & Dragons- 3rd and 3.5th editions.

===Exploding dice===
==== Roll again====

On rolling a certain number, the dice may be rolled again, and re-rolled for as long as the ”exploding” number keeps coming up. Each roll contributes more to the total.

Examples: On an attribute + D10 roll, the player rolls a 0. She adds 10 to her total and rolls the dice again, coming up with another 10, after which she gets a 3 - netting a total sum of 23. In a WoD-style dice pool roll, the player rolls two 0's, which net him one success each and allow him to reroll them.

==== Roll again and multiply====

As above, but the ”exploding number” itself isn't added to the total - instead, each time it is rolled, it increases a multiplier that will be applied to the final roll.

Example: On an attribute + D10 roll, the player rolls a 1. She rolls again, and gets another 1, and another. Then she gets a 9. Since she rolled three 1's, the 9 is multiplied by 3 (or, as in Ars Magica, by 2^3 = 8). 

Game examples: Ars Magica.

===Extra effects===

If a certain number is rolled, the character manages to do something extra on the side, though the roll itself may still be a failure.

Example: On a D100 roll, 11s, 22s, 33s and so on produce an extra effect.

Game examples: Unknown Armies.