Causes a devastating explosion of flames, dealing extremely high fire damage on a total of 73 squares around the caster. The spell deals about 5-10% more damage than Rage of the Skies, but its area of effect is smaller.
This spell, together with Rage of the Skies, replaced the old Ultimate Explosion spell in the Winter Update 2007. Hell's Core is considered to be less useful overall, due to dealing virtually equal damage, while costing almost twice as much mana and the fact that many high-levelled monsters are immune to fire damage. Hell's Core is the sorcerer's equivalent of the druid's Eternal Winter, compared to which it costs 50 mana more, but has a larger area of effect and deals about 10% more damage. Casting this spell puts ALL combat spells on a 4-second cooldown.
Prior to the Vocation Adjustments Update, Sorcerers could use either Hell's Core OR Rage of the Skies. If the player had learned both, they could switch between them by speaking to Zoltan and paying 500 gp.
In the past, this spell used to have a different animation: