IgniGar is a legendary Runeword created by combining a Igni Rune of Ritual and a Gar Rune of Invocation.
How to Create IgniGar
You can create IgniGar by adding the legendary Igni Rune of Ritual and the magic Gar Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Igni - Stores offering every 0.3 seconds. Cast a non-Basic Skill to gain the stored offering. (Up to 500 Offering). (25)
Gar - Gain 2.5% Critical Strike Chance for 5 seconds, up to 25%. (25)
Overflow
IgniGar can not overflow because the amount of Offering you receive from the Igni Rune exactly fills the required Offering of the Gar Rune.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.