This is the ICON system for Last Unicorn Games. This is a D6-based pool system against difficulty set by the GM.
The basic formula for tests is to roll a number of D6 equal to your attribute. Only the highest die is counted. After adding the skill to the result, the total is compared to a difficulty. The system requires that one of the dice be different to denote a Drama die. If the result of this die is either a 1 or a 6, this determines that the outcome was either extremely good (6) or extremely tragic (1).
This system was used for the Star Trek games from Last Unicorn as well as their limited Dune RPG.