Monday, May 16, 2016

Bonus and Penalty Dice

These are some rules from my fantasy heart-breaker which I thought could be usefully layered over any system that uses a d20 + modifiers vs. a target.

Circumstances or character aspects may influence your chances of success or failure on a check. These are represented with bonus and penalty dice, which are six-sided. They may be denoted as +#d or -#d, respectively.

When you make a check with bonus dice, if any of the bonus dice come up 6, you succeed, regardless of your d20 roll. Conversely, if you make a check with penalty dice and any of them come up 1, you fail, regardless of your d20 roll.

If you have both bonus and penalty dice, they cancel each other before rolling. For example, if you have +2d and -3d, roll just 1 of penalty die. You never roll bonus and penalty dice at the same time.

If any bonus die comes up 6 and your d20 check also succeeds, that is a critical success.

Likewise, if any penalty die comes up 1 and your d20 check also fails, that is a critical failure.


If something in your system would call for a +2 or -2 on a d20 roll, you can substitute one of these dice. They turn out to be about the same - the left column here is a target number, and the header is a character's modifier.

Those hit numbers work because the bonus die only matters if the d20 roll misses. The highlighted parts are where most rolls seem to happen, at least in the early levels of the game, or in a lower-powered one.

These dice become less important for skilled characters to succeed, but do help in avoiding mistakes and in driving crits. They reward less-skilled characters for seeking them out.

Almost everything in my game got converted into bonus and penalty dice, so the d20 rolls changed infrequently, since they were based on ability scores. You don't have conditional modifiers to tack onto the roll - they are all individual dice, with no math involved.

That also means there aren't something that would translate as conditional +1 modifiers, but I have never much liked them anyway.

Some character aspects could give bonus dice, but mostly they're situational. Charging? Bonus die for everyone! Attacking something invisible? Well, have a couple penalty dice.

Also note you can't crit or fumble without an extra die. You really want to seek out bonus dice for this reason, either to line op the crit, or negate the possibility of a fumble.

Adding more dice in either direction scales the chance of success or failure interestingly, though I think getting more than 3 in either direction would be rare.

  1. 17%
  2. 31%
  3. 42%
  4. 52%
  5. 60%
  6. 67%

I also ended up getting rid of a lot of level bloat by relying on these dice. If you were facing off against a thing of a substantially higher level, you got a penalty die, and it got a bonus die. Same thing if weaker opponents were facing you.

Monday, May 9, 2016

Fun With Some Blunderbusses

Some magical blunderbusses (blunderbi?) because why not. Assuming 5e but you're adaptable.


When you roll a natural 1 on an attack roll with this weapon, roll on the Wand of Wonder effects table.


Attacks with this gun deal an extra d6 thunder damage. When it rolls a natural 1 on an attack roll, all creatures in 10 feet of you (including yourself) must pass a DC 15 Fortitude save or take d6 thunder damage and be deafened for a minute.


Advanced artillery now available in convenient liquid form. Poured from its bottle, this thick, milky liquid permanently forms into a serviceable large bore shotgun in a round. If you drink it (and why wouldn't you) you can spit shot for a minute (assuming you have shot).


You can use rations as ammunition for this weapon. If you do it deals an extra d6 acid damage and is terrible.


Muzzle acts as a bag of holding, but fires a random item from its store on an attack roll of 1.


If you roll doubles on your damage dice on attacks with this weapon, roll them again.


This weapon is named Günter. He has Intelligence 10, Wisdom 11, and Charisma 9. He can speak, read, and understand common (but he can't speak on a turn he's used to attack, because his mouth is firing shot, of course). Hearing and normal vision out to 120 feet. Neutral alignment and seeks his creator.

Günter can chew up pretty much anything for use as ammunition, but he prefers wine casks and coal.