[Endoperez]

There is no simple spell anyone can use. Not even a simple spell any nation can use. There are spells and items that most nations can use, or spells and items that most nations can use if they happen to get one of many kinds of common independents (Endless Vineskins come to mind). But that spell would be quite powerful, and thus require at least level 2 in some path, and so would be out of reach of some nations. Perhaps many nations, if it required something most nations don't have easy access to.