Windbound

Meta currency is referring to the blue shards you collect from blue pots, diving where the blue bubbles emanate from certain area in the water, activating towers etc. It’s surprising how quickly you can save up shards to well over 5k especially if you are thoroughly exploring all islands in each of the 5 chapters. You may get lucky and come across the blessing at the end of a chapter for finding extra shards in which case be sure to equip this as it nearly doubles the shards you find. I managed to save up 7k shards by chapter 3 with that blessing equipped.