Some sort of rare gem/ore that when processed could be used as a battery for certain devices, and gets recharged during the time of day when used. Sunstones charge during the day. Moonstones charge during the night. Neither charge when it's cloudy/storming. Can't be charged/used at the same time. [So you can't install a sunstone battery in an item during the day, and expect to be able to use it without draining battery]
If you think about it though, I've seen other sci-fi games use alien stones to power items, for one example Eridium from Borderlands. It's not Sunstones as we know them. It's like an alien stone that's irradiated and rechargable in a specific way.
Soooo...they provide energy? Depending on time of day? Like a...solar panel? I will admit...it would look way cooler than a solar panel!
The solar one I could bye into easily.. but it will take a lot of work to make me buy into a moonstone...(unless you give me a Nidorino...) Also Eridum sucked simply because.. WHY is the innovatory maxed w/ 27 slots! How do the expect me to collect all the uniques and legendaries!!!!!!!!!!!!!! sorry a little rage...
"It's a solar panel.. in your pocket!" "In my pocket?" "Oh yes! They come in different coloration's, red, blue, green, black, yellow, orange, pink, and clear!" "Oh wow-y!" "And we even have a night version, so you can't waste all that night energy!" "Oh boy!" "They're called sun stones, and moon stones, we can put stickers on them, make them into dogs!" "Oh yay!" "WE CAN EVEN MAKE THEM TO SUMMON THE DEEP DARK LORD OF EVIL AND SUMMON DEMONS INTO THE REALITY OF OUR LIVES!"
Awright! Yer sunstones done! So whaddya want me to do with it? Let darkness reign. And in the darkness, let evil grow!
