Bones: Customizable Dice Roleplaying Game (2004)

Publisher's blurp:

BONES is a fantasy roleplaying game in which characters, monsters, equipment, and obstacles are represented by customized six-sided dice. Simple, elegant mechanics keep the game moving and the action tight, and the rules include player narrative control, a mechanism for adjudicating actions and events that take place between play sessions and a modular system for creating non-player characters and monsters on the fly. With a magic system that allows complete customization, BONES belongs at your gaming table or at least in your collection. Even the GM gets to play. Embrace the dice and face your destiny!

Use with blank six-sided dice (and labels) or regular six-sided dice.

Each character die has one face which is marked with a +, (the icon for universal success) and one face marked with either a triangle (the icon for mental success) or a square (the icon for physical success).

The remaining four faces can be customized by the player, as he sees fit.

Beginning characters start with four character dice, gain icons and dice as they gain experience and temporarily lose dice when they are injured.

Characters roll their bones (dice) once per task they are attempting and compare the number of successes they have rolled to the opposing roll to determine the results of their efforts.