If someone plays Ride the Wind on Overzealous Fan after strike/defend phase starts, does Overzealous Fan trigger its 'When I Defend' ability?

Ruling: Yes, Overzealous Fan will trigger its "When I Defend" ability. "When I Defend" triggers happen whenever a unit enters combat/the battlefield during combat, not just at the beginning of combat.

Sequence:

• Ride the Wind is played as an action
• Opponents can respond with reactions (e.g., Shakedown) to remove Overzealous Fan before it arrives
• If no responses, Ride the Wind resolves and the chain closes
• Overzealous Fan arrives at the battlefield and gains defender designation
• "When I Defend" trigger occurs in the cleanup after the chain closes

Nuances:

• The existing chain must resolve first before Overzealous Fan arrives and can trigger
• If a unit becomes located at a battlefield via a reaction speed spell/ability (like Hidden Here to Help), the trigger goes on the chain in the cleanup after that spell/ability resolves, which may be mid-chain