Fire Emblem: Heroes is out in the world, and unlike Super Mario Run, it's a genuine free to play game. Like any free-to-play game, Fire Emblem: Heroes has a sizable stack of currencies. Orbs are among the most useful: they're very limited, unless you decide to shell out cash. They're the only way to summon heroes, which you'll need to do to expand your roster and increase the flexibility of your teams. You should use your first round of orbs to summon up some heroes, because you'll need them to keep fighting.

Source: Forbes February 04, 2017 19:07 UTC