Your aspect aptitude has an additional affinity option.
Extra Aspect Affinity (inscription)
Select an additional aspect affinity. Your inscriptions have been extended with filtering pathways to align energy channels with the selected aspect affinity.
Prerequisite: Aspect Aptitude class feature.
Benefit: You get the selected aspect affinity as an option when bestowing aspect affinity via the Aspect Aptitude class feature. Additionally, you can use the Aspect Aptitude class feature on an additional channel. If you know multiple aspect affinities, you can only pick a single affinity for all your aspected channels.
Special: You can gain Extra Aspect multiple times. Each time you take the feat, it applies to a different aspect affinity.