The Hunt Prey feat gives a Ranger bonuses against a creature, they seem to be able to re-designate a target endlessly it seems within the same day:
You can have only one creature designated as your prey at a time. If you use Hunt Prey against a creature when you already have a creature designated, the prior creature loses the designation and the new prey gains the designation. Your designation lasts until your next daily preparations.
This Feat is tagged Concentrate and Ranger.
A couple of questions to clarify things I'm not sure on:
- Can a Ranger endlessly re-designate targets to hunt during a day?
- How many actions (if any) is it to designate a new target?