When is a target chosen for Xaxos's Flare?

Name
When is a target chosen for Xaxos's Flare?
Details
When casting Flare (Cast: Reveal the top card of the turn order deck, and then place it back on top of the turn order deck. If you revealed a player turn card, deal 3 damage. Otherwise, deal 1 damage.), Xaxos chooses a target for the damage after revealing the top card of the turn order deck.
Cards
Flare
Mages
Xaxos (AE)
Nemeses
Other
References
https://boardgamegeek.com/article/26914503#26914503