The only currency in the game is gold. All abilities and materials can be purchased with gold.
There are many ways to earn gold. Gold can be earned by hitting NPC's in the game or by collecting chests. The following methods are recommended in order to earn more gold.
1- The in-game missions.
2- The Baron's NPC ship. (From 3/2 and up maps)
3- You can participate in guild chest events, this event happens on some weekends.
4- Event NPC's or event chests can be collected whenever there is a new event.
5- Gold packages can be purchased for a fee from the store.