Its Swedish roleplaying system called "EON" that uses D6 dices. But since they dont want an dagger to always be "none dangerous" if u are using leather armor. They are using a system that is "ob" with is short for endless. So if a short sword that does ob2d6 damage, if you roll a 6 on a dice then remove that dice and add 2 new ones. And this loop goes forever untill there are no 6 showing. on any dices. So lets say you role 2d6 and u get "dices showing a 4+6" then u rerole that 6 dice and ad a new dice. But the 4 is still there. And the 2 new dices shows a "5+3" so the end damage from "ob2D6" ==> 4+5+3= 12 And ofc u can role a 6 on your dice and then role a 1+2 = 3 and get a lot lower value then the 6 you roled in the begining.