"The Kindly Lord does not issue invitations to their court lightly. I suggest you accept."

Talion's Messenger

Flying
Whenever you attack with one or more Faeries, draw a card, then discard a card. When you discard a card this way, put a +1/+1 counter on target Faerie you control.

Wilds of Eldraine Promos

Wilds of Eldraine

You don't choose a target for Talion's Messenger's ability at the time it triggers. Rather, a second "reflexive" ability triggers when you discard a card this way. You choose a target for that ability as it goes on the stack. Each player may respond to this triggered ability as normal.