Abyssal Rune

Source
This item is found within the Trial of the Champion in both Eadric's Cache and Confessor's Cache.

Effective Spell Power
The effective spell power granted by this item is affected primarily by cast time. This trinket benefits more from shorter cast times. The formula for calculating the amount of effective spell power granted by this trinket is: E = 590 * 10 / (45 + (t / 0.25)) Where E = effective +spell power t = cast time The following Java Program can be used to obtain a table of effective +spell power for different cast times. public static void main(String[] args) {      float time; float effective; for(time = 1; time < 6.5f; time += 0.5f) {              effective = 590 * 10 / (45 + (time / 0.25f)); System.out.println(" " + time + " " + effective + "  "); }  } This gives the results below: