Siege Firestorm Effect
Stack Size: 20Your Firestorm becomes a flaming siege assaultRight click this item then left click a Firestorm Gem to apply it.
Siege Firestorm Effect is an alternate skill effect for 
FirestormFirestormSpell, AoE, Duration, Fire
Level: (1-20)
Cost: (13-25) Mana
Cast Time: 0.75 sec
Critical Strike Chance: 6.00%
Effectiveness of Added Damage: 80%Requires Level 28Flaming bolts rain down over the targeted area. They explode when landing, dealing damage to nearby enemies.Base duration is 1.40 seconds
Deals (23-361) to (35-541) Fire Damage
One impact every 0.15 seconds
Base radius is 1.3 metres
First Impact has 100% more Area of Effect
First Impact deals 325% more Damage with Hits and Ailments
Maximum 3 Firestorms at a time
Additional Effects From 1-20% Quality:
Base radius is (0.01-0.2) metresPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket.
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It can be purchased in the shop for 25 points.