Virtue Limited Perfect Defenses
In this variation on the standard rules, perfect defense charms use their pre-errata essence costs, but players must also spend a Virtue channel, with an appropriate stunt, in order to activate their perfect defense to negate an attack.
The 2.5 errata changes to the essence cost of perfect defenses, intended to prevent perfect spamming, made perfect defenses hugely disruptive to an otherwise fairly functional mote economy around the numerous other combat effects in the game. By attaching a cost in an under-utilized by still very limited resource instead, the same goal is achieved without the unfortunate side effects, while simultaneously making the use of the game’s signature effect more likely to be a high impact moment at the table.
The main consideration with this is that because Virtue channels take more than a little down time to recover, chronicles with a lot of combat can see characters reaching their most challenging battles with very limited resources for perfect defenses. Storytellers should be aware of this, and either pace their battles accordingly, or offer something like Virtue Recovery Stunts to help players manage this resource.
Additionally, some care must be taken around combinations of charms which allow a character to quickly and easily recover Virtue channels (particular attention should be paid to Solar Integrity charms, Crane Style martial arts, and a variety of Sidereal charms). If you have legalistic players who can’t or won’t refrain from making broken combos out of this, it may not be for you.
Note that the verbiage “to negate an attack” is added to allow for freer use of perfect defense charms for dramatic and utility purposes. This applies to things like parrying a waterfall in a training montage or dodging the rain, but is also a specific nod to the use of the Alchemical charm Precalculated Evasion System with the Trasphase Engine submodule to pass through barriers during movement.