Pretty sure on the answer here, but there was enough uncertainty in Discord to post here to make things official:
Does Shield of Faith prevent Ricochet from being played at all (by both sides, of course)?
Shield of Faith:
Dudes cannot be aced or discarded during this shootout, except as a casualty for losing the round or due to their owner’s card abilities or traits. Reduce your casualties this round by 1.
Ricochet:
The cheating player discards their shooter. If your hand is legal, you do not take casualties this round and draw a card.
Is your question whether is can be played at all?
Or whether Shield of Faith blocks the first effect (discarding the shooter) but not the second effect (negating casualties and drawing a card if legal)?
It certainly blocks the first effect, but yep, my question is if it can even be played at all, since its first sentence requirement cannot be met.
Seen and under review by the Rules Team.
You are required to be able to fulfill the first sentence of Ricochet in order to play it.
The cheating player discards their shooter.
Shield of Faith prevents any discards or acing that don’t come as Casualties or from their controller’s own card abilities or traits.
Therefore neither player can play Ricochet in a Shootout after Shield of Faith has been used.