For the Call of the Hunt feature of the Path of the Beast barbarian, do the willing creatures need to want -- or even be ABLE -- to make attacks?

Question

Call the Hunt, the 14th-level Path of the Beast barbarian feature, says:

When you enter your rage, you can choose a number of other willing creatures you can see within 30 feet of you equal to your Constitution modifier (minimum of one creature). You gain 5 temporary hit points for each creature that accepts this feature.

This seems to suggest that any creature seen within range is eligible to accept the feature and thus grant you temporary HP. From most obvious to most absurd, this might be:

• your ally
• your ally's familiar
• an NPC bystander
• a passing squirrel, dragonfly, bird, or other animal

However, in addition to providing a benefit to the barbarian, this feature also provides a benefit to the willing creature:

Until the rage ends, the chosen creatures can each use the following benefit once on each of their turns: when the creature hits a target with an attack roll and deals damage to it, the creature can roll a d6 and gain a bonus to the damage equal to the number rolled.

Clearly, this benefit is only relevant for a creature who is able to make an attack and desires to do so.

Therefore, I wonder: Is a creature only eligible to accept this feature if they're able to benefit from it directly? That is, do they need to be able to make an attack (unlike many familiars) and do they need to have an enemy present that they're ready to attack (unlike most bystanders and random fauna)?

Answer 1

The only requirement to accept a barbarian Call the Hunt is being a willing creature.

The rule you quoted contains all the relevant information needed to assess if a creature can benefit from Call the Hunt (emphasis mine):

When you enter your rage, you can choose a number of other willing creatures you can see within 30 feet of you equal to your Constitution modifier (minimum of one creature).

A creature\$^\dagger\$ must be willing\$^\ddagger\$ to be eligible to receive Call the Hunt. There are not any other requirements such as being able to attack or having other creatures (hostile or not) close to them. If other conditions should be met, the description would have explicited so, by stating for example "When you enter your rage, you can choose a number of other willing creatures that can perform the Attack action and that you can see within 30 feet of you equal to your Constitution modifier (minimum of one creature)." or something similar.

Deciding if creatures (e.g., local fauna) around the fight but not directely involved are willing or not is a DM's call: some may be frightened and run away, while others may be feel threatened and be ready to defend themselves.

As nick012000 suggests in the comments, hostile creatures may accept this increasing of the barbarian's HPs in order to deal more damage. Indeed, the description says "when the creature hits a target with an attack roll [...]" and does not prevent the target of these attacks to be the barbarian. The bonus damage is 3.5 (on average) once on hit per round, until the rage ends. If the rage lasts for 2 rounds or more, then this could be a good strategy.

Moreover, the wording describing the effects of Call the Hunt on other creatures says (emphasis mine):

Until the rage ends, the chosen creatures can each use the following benefit once on each of their turns: [...]

The creatures can use the benefit, it is not mandatory to use it: if they can not attack (see toad, for example) they will not benefit from the d6 bonus damage.

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\$^\dagger\$ See this Q&A What is the definition of "creature" and is it used consistently? (and related posts) for a discussion about what is a creature in game terms.

\$^\ddagger\$ See this Q&A Can you make an unwilling creature willing? In other words, what defines “willing”? for a discussion about willing creatures as target for spell and/or effects.