Hey, it seems to not be the case but I wanted a second opinion.
World Tree Barbarian's level 3 Vitality of the Tree, Life-giving Force subsection begins with:
At the start of each of your turns while your Rage is active, you can choose another creature within 10 feet of yourself to gain Temporary Hit Points.
That seems to mean in Round 1, if the barbarian rages and attacks his first turn, the barbarian can not also use Life-giving Force that same turn (but still gets the Vitality Surge for himself) since the rage was not active at the beginning of his turn.
Hey, it seems to not be the case but I wanted a second opinion.
World Tree Barbarian's level 3 Vitality of the Tree, Life-giving Force subsection begins with:
That seems to mean in Round 1, if the barbarian rages and attacks his first turn, the barbarian can not also use Life-giving Force that same turn (but still gets the Vitality Surge for himself) since the rage was not active at the beginning of his turn.
That's correct. You can't use that on the turn when you activate Rage, because by definition Rage wasn't active at the start of that turn.
But you should keep in mind that the 2024 version of Rage can last up to 10 minutes and can be maintained out of combat.
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