Effect: Your character’s Nimbus has distinct and powerful effects on witnesses. At one dot, add two to your character’s effective Gnosis when determining her Nimbus Tilt. At two dots, add four to her effective Gnosis for that purpose. Additionally, increase your effective Gnosis by this same amount for the purposes of determining the effective range of flaring your Nimbus. This does not affect the duration of your Nimbus Tilt.
Lastly, add your dots in this Merit to any rolls to flare your character’s Nimbus, resist another Mage's (or other supernatural creature's aura) Nimbus, or on any Clash of Wills resulting from flaring your Nimbus.
For example, a Gnosis 1 Mage, with Potent Nimbus ••, would treat their Gnosis as being 5 for purposes of determining the strength of their Nimbus Tilt, and would affect witnesses up to 50 yards away. They would add +2 to the roll to flare their Nimbus, and any resulting Clashes of Will, and it would last one round by default.