You gain regeneration when you are bloodied. However, this is a Stance power, which means it lasts until the end of the encounter or until you use a different Stance power.
In other words, until the end of the encounter or until you use another Stance power, any time you drop below half hit points you gain regeneration 2 + Con bonus. When you stop being bloodied, you stop regenerating. If you are later bloodied again, you start regenerating again.
I particularly liked this post.
You are under the effect of the power until you change your stance or the encounter ends. However, you only regenerate when you are bloodied.
So it would go like this while the power is active:
Start of turn: Are you bloodied? Yes, then regenerate 2+Con Mod; No, then no effect this turn. Rinse and repeat.
Here are the most useful forums that had postings on the subject.
- Boundless Endurance Question
- Regeneration - for how long?
- Boundless Endurance
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