Twisting Fate

You have a connection with fate that allows you to twist it at appropriate moments to alter the course of events.

• You have 3 Fates you can alter: your attack rolls, your ability checks, or your saving throws. Each Fate is either a "Critical Fail" (natural 1 on a d20) or a "Critical Success" (natural 20 on a d20) at any given time.
• When you first gain this feat, each of your three Fates is a "Critical Fail" (natural 1); at any point if you roll a Critical Success (natural 20) on the appropriate type of roll, you can choose to bank that "Critical Success" by swapping it for your stored "Critical Fail" of the same roll type. The stored Fate can be used to swap out your rolls of the same type with the opposite type of Critical when rolled.
• Fates you have in store are maintained until you choose to replace them by swapping them with the opposite type of Critical roll, indefinitely.
• Critical rolls from inconsequential activities (i.e. actions that will not change the course of events) may not be banked; only critical rolls that may meaningfully alter the course of events will do this. [This is at DM's discretion, but should reflect whether the consequences of the "critical" to be banked are reasonably equivalent to the importance of the critical they replace. The Fates insist on balance!]
• Each type of Fate may only be swapped once per Long Rest.