Play details: Every turn, players simultaneously choose which of their power cards to play, paying energy to do so. Using combinations of power cards that match a spirit's elemental affinities can grant free bonus effects. Faster powers take effect immediately, before the Invaders spread and ravage, but other magics are slower, requiring forethought and planning to use effectively. The Invaders expand across the island map in a semi-predictable fashion. Each turn they explore into some lands (portions of the island); the next turn, they build in those lands, forming settlements and cities. The turn after that, they ravage there, bringing blight to the land and attacking any Dahan present. (Who then retaliate.)
The game escalates as it progresses: spirits spread their presence to new parts of the island and seek out new and more potent powers, while the Invaders step up their colonization efforts. Each turn represents 1-3 years of alternate-history.