View Full Version : d20 replaced by 3d6... with explosions.

2015-08-19, 11:05 PM
This is for Pathfinder, DnD 3.X, DnD 5E, and most any system that relies on the d20.

I like d20, in fact one of my favorite systems (Star Wars: Saga Edition) is a d20 based system. However, there is one major problem I have with d20... is that it's too random. The 5% chance of automatic success or automatic failure that comes from rolling the die on a 1 or 20.

I recently tried GURPS for the first time, which uses a 3d6 system... and while I liked the average nature of the rolls, I really dislike roll-low systems in general. Secondly the GURPS system, shockingly, isn't random enough for my taste. Sure the odds of a 3 or 18 coming up are 1/10th that of a 1 or 20 on a d20 system, but it doesn't have the same instinctive whoa! factor of rolling a 20 or a 1.

I know that there are alternate rules to turn DnD 3.X into a 3d6 based system, but they require quite a bit of tweaking of the normal rules for things like critical threat ranges and so forth. Plus there still isn't the thrill of rolling a 20...

What I propose is to use 3d6... but have the die explode on a roll of a 6. Hits greater then the current critical threat ranges (18, 19, 20, and so forth) are critical threats. Plugging this into any dice to see how it performs compared to traditional 1d20 and 3d6 actually make it look really attractive. While there is a statistical higher probability of success (the chance of rolling 11 or greater is 57.41%, this is basically the equivalent of giving everyone a +1 1/2 bonus to all rolls), other factors like chance of a critical hit with the current threat ranges actually fall close enough to the d20 values that I'd be comfortable without altering them.

18 or better - 17.05% (compared to 15%)
19 or better - 13.97% (compared to 10%)
20 or better - 11.42% (compared to 5%)

Plus exploding dice mechanics allow for thrilling rolls at times, and allows for higher numbers then the straight 3d6 would have.

What are your thoughts with this type of system?

2015-08-20, 04:44 AM
Burning Wheel already has a system like this, and they nailed something really important about it.
Dice do not explode for free
You have to expend a point (Artha I think it was called?) in order for it to be possible. The danger of giving free explosions* is that it would be too easy to, well, explode the dangers or other trials. Not to say it wouldn't be fun, but it would be straight up unbalanced unless handled very carefully.

*Free explosions, sounds like something Torgue would do!

2015-08-20, 06:00 PM
joke/Exploding dices is always going to cost at least the price of the exploded dice.
Also it is unsafe to use explosives you might get blind./joke