Say the PCs find a hidden console with some buttons. They learn the right order to press the buttons, and a section of the floor disappears (this happened in the second playtest session I wrote about). As GM, I don’t have the players specifically tell me where they’re standing. Instead, I give one player an XP and say, “unfortunately, you are standing directly over this new hole in the floor.” Now, if he wanted, the player could refuse the XP and spend one of his own, and then he would say, “I leap aside to safety.” Or, he could just make the defensive roll that the GM calls for and let it play out.
At first this just seemed like D&D and Pathfinder's Hero Points variant rule, but Hero Points come across as more of a "get out of jail free" card for players, and not the narrative currency that XP points will be in Numenera. Furthermore, XP points will still be used to "increase character abilities... or advance in levels."
The idea of XP as a currency to drive two-way narrative dialogue intrigues me, and as I've only played various d20 systems, have not seen this before. Is this concept new to Numenera, or has it appeared before in other systems? If so, in what ways has the concept evolved over the history of roleplaying games?