This is a resource management game. As such, you harvest resources and craft items for additional higher level craft items. Energy resets every 3 hours, side islands/adventure islands give additional energy opportunities. This is a fun game, but don't be expecting to play the game for hours continuously. I sign into the game about 4 to 5 times daily, play for about 15 to 20 minutes. I can complete the adventures without spending money, and have been on the adventure leaderboards.