CirQua is a rare Runeword created by combining a Cir Rune of Ritual and a Qua Rune of Invocation.
How to Create CirQua
You can create CirQua by adding the magic Cir Rune of Ritual and the rare Qua Rune of Invocation to a two-socketed Helm, Chest Armor, Pants, or Two-Handed Weapon.
Cir - Cast the same non-Channeled Skill 3 times in a row. (25)
Qua - Restore an Evade charge and gain 6% Movement Speed for 5 seconds, up to [6*5]%. (400)
Overflow
CirQua can not overflow because the amount of Offering you receive from the Cir Rune exactly fills the required Offering of the Qua Rune.
Overflow occurs when your Ritual generates more Offering than required for the Invocation. The overflow effect is proportional to the amount Offering overflows.