# What kinds of effects can modify a die roll?

After you roll a d20, there are some effects that can modify the result before the calculation is made. Is this a complete list?

• If you don't like the roll (before you know success or failure), throw it away and roll it again
• If you don't like the roll (after you know the result), throw it away and roll it again
• Roll it again and take the better result (oath of enmity)
• Roll it again and take the worse result (various curses)
• replace a die roll with one you rolled before (dice of auspicious fortune)
• add a number to the die roll (heroic effort, adept's insight)

And I think these only apply to a damage roll:

• Brutal
• if it's N or below, re-roll until it's N+1 or above
• if it's N or below, throw away the old roll and re-roll once, taking the result no matter what
• if it's N or below, change to N+1
• if it's the maximum value, roll again once and take the sum
• if it's the maximum value, roll again, take the sum, and repeat if it's maximum value (vorpal/explosive)
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* Event: Someone dumps the pizza box on top of the dice and the board, scattering everything everywhere. – Rob May 3 '12 at 14:38
Nitpick: With the dice of auspicious fortune, you use the result you rolled earlier instead of rolling the attack, not after you see it and dislike it. So it doesn't exactly fit in this list (since you're not modifying the result, you're predetermining it). – dpatchery May 3 '12 at 15:01
suggestion: take all of those out and put them in a single comprehensive CW answer – wax eagle May 3 '12 at 15:28
What problem are you trying to solve with this? – Pat Ludwig May 3 '12 at 15:59
@Snowbody my suggestion is a bit different than CWing the question. My proposal is to create one single answer as CW it and maintain it as a list of all possible ways to modify the roll. blog.stackoverflow.com/2011/08/the-future-of-community-wiki – wax eagle May 4 '12 at 12:36