Hunter (Mercenary) has a clause in his first unique where he gains a bonus turn whenever Marked expires on an enemy if he has 15 or more stacks of Target Practice, however this bonus doesn't trigger ...
Ideas
I attached a video of a battle where there's two different instances where marked expires from an enemy death while Hunter has 15+ stacks of Target. The first instance (around 1:10) does not have the bonus turn trigger, while the second instance (around 1:45) does have the bonus turn trigger. The bonus turn does trigger, but not consistently.
https://youtu.be/X1WpPrfHPJU?si=KXiOiQiH0-a6wK8b