Light Essence is the cosmetic currency of Rise in Time. Most player and tribe icons in the shop are priced in it.
Earning
Winning a ranked Dominion round pays 1 Light Essence. Events such as Dominion Day can pay it out as well.
Spending
The shop sells 11 icons for Light Essence, from 100 to 1'500 Light Essence each: 10 player icons and 1 team icons.