Mental Adaptability Feat

Prerequisite: Inventor

• You've found ways to think outside the box, making connections that other (lesser) minds can never seem to understand. When you make an Intelligence, Wisdom, or Charisma saving throw, you can roll all three and pick the highest result. Once you do this, you can't do it again until you finish a long rest.
• You can select an additional upgrade that is not from your subclass list, so long as you can apply it to something in your possession. This upgrade can't be a level-restricted upgrade.

Source: KCCC, page 126