Mana

From The Five Pillars

In The Five Pillars mana is the source mages use to cast a varity of spells. You get mana each turn from your nodes, and if you manacharge you get x2 your normal income.

You will get the most mana out of a certain kind of manaland if it's at 25%. Mostly 30% main manaland and 15% for two neighbouring colours are adviced. You can differ of course, but generally speaking it's best to stay under 50%, otherwise you will be wasting land.