A War Ring adds an extra crit die as a property and does this as a daily:
Use this power when you score a critical hit with a weapon or implement. Add 2 extra dice of critical hit damage based on the weapon or implement. If your weapon or implement deals no extra damage when you score a critical hit, deal an extra 2d6 damage when you score a critical hit.
If you've reached at least one milestone today, instead of rolling the extra dice of critical hit damage, deal extra damage equal to the maximum value of those dice.
I was thinking of taking one, but I'm not sure how it works. If I have a Vicious Weapon +3, would a critical hit (with a milestone) mean I roll 3d12 and get 3d12 that are maxed out, or would all six of them be maxed out? In other words, does that last blue line only apply to the dice granted by the ring, or would it trigger for any dice that I get on a crit?