Focus Core

A focus core makes up a focus along with an inscription.

there are 4 focus cores in the PvP Equipment window.
 * Health +30
 * Health +45 (while under effect of enchantment)
 * Halves casting time of spells (chance 10%)
 * Halves casting time of spells of item's attribute (chance 20%)

after choosing the item, the focus core and the inscription, press create and you will have item with focus core.