D&D General A d20 fail-forward dice method

[clearstream]

One problem that interests me is that of producing results including at least success, success with hindrance, and failure, from a d20 system. Talislanta has one approach, which is similar to flipping the D&D DCs into penalties instead of targets, in order to have fixed targets (e.g. 11+ is a full success.) Elsewhere I've proposed a way to do that for 5e. For those not familiar with the relevant DMG rules, 5e does have a nuanced results method, but the break points are clunky. They're hard to remember to apply at the table, and the range for success with hindrance is narrow.

Others have suggested rolling a side-die and reading nuance off it (e.g. one rolls a d8 and a 1-4 makes a success into a success with complication.) Taking that as my point of inspiration, I had the thought to use the following.

With the d20 also roll d8

• d20 alone succeeds = full success
• d20 + d8 succeeds = success with hindrance.

For advantage and disadvantage, the d8 applies to the kept die. The probabilities are tidy and can be tuned by choosing a d6 or d10. Say the DC is 10 aka "easy". Using a d8, there's a 55% chance of full success and 22.5% chance of success with hindrance. That's if the character has no applicable modifier. As an aside, I believe it is easier to add a number visible on a secondary die rather than a fixed number like 5.

This is quite similar in upshot to the DMG rules. What it is doing is broadening the range for a success with hindrance, and making it easier to identify nuanced success consistently at the table. While this method could stand on its own, one aim is to allow use of other published material unmodified. (An impediment to the "flipped indexes" I've elsewhere proposed is that work is needed to convert DCs.)

Anyway, posting here for thoughts, analysis and criticisms.