Does Draven have his increased Might when triggering Legend Volibear's 'when you play a Mighty unit' ability?

Ruling: Yes, Legend Volibear's trigger sees Draven when he is already on the board with his full Might, so the ability will trigger.

Sequence:

• Draven is played from hand (where he is Might 3)
• Draven enters the board and gains his increased Might from his passive ability
• Legend Volibear's "when you play" trigger checks and sees Draven with his full Might

Nuances:

• While Draven is in hand, deck, or trash, he is only Might 3 for effects like Baited Hook or Aurora
• Draven only gains his increased Might once he is on the board