Anointer of Valor

• WWizards of the Coast2020-11-10
  Official Ruling
  Anointer of Valor's triggered ability triggers when any creature attacks any player or planeswalker.
• WWizards of the Coast2020-11-10
  Official Ruling
  If you choose to pay , a second triggered ability triggers. Players may respond to that reflexive triggered ability before the +1/+1 counter is put on the creature.
• WWizards of the Coast2020-11-10
  Official Ruling
  You can't pay more than once to put more than one +1/+1 counter on the attacking creature.

Rulings via Scryfall