A Frosthorn executioner

==Notes=
 * Frosthorn executioners and nightgores are triggered spawns - after clearing the packs of Frosthorn shadowgores/stormcallers/vindicators from around and, a group of executioners and nightgores will spawn.  Killing the southern bunch of executioners/nightgores has a chance to spawn , the northern bunch has a chance to spawn.
 * Possible classes Berserker, Warlock