Sextant of Unstable Currents

Sextant of Unstable Currents is an epic trinket for DPS casters.

Source
This item drops from Fathom-Lord Karathress in Serpentshrine Cavern.

Effective Damage
The effective +damage granted by this trinket is achieved in a method almost identical to that of Shiffar's Nexus-Horn. Essentially, to get the most out of this trinket, you want shorter cast times, and higher crit.

The formula for calculating the amount of effective +damage granted by Sextant of Unstable Currents is -

E = 190 * 15 / (45 + (t / (0.2 * c)))

Where...

E = effective +damage t = cast time c = critical strike chance

The following Java Program can be used to obtain a table of effective +damage for different casting speeds: public static void main(String[] args) {       float crit; float time; float effective; for(time = 1; time < 6.5f; time += 0.5f) {           for(crit = 10; crit < 101; crit++) {               effective = 190 * 15 / (45 + (time / (0.2f * (crit / 100)))); System.out.println(" " + crit + "  " + time + " " + effective + " "); }       }    }
 * 1.5s - Scorch, Searing Pain, Wrath
 * 2.0s - Lightning Bolt
 * 2.5s - Frostbolt, Shadowbolt, Incinerate
 * 3.0s - Fireball