Can Azir - Ascendant's ability be activated while he is exhausted, and how does the ability work when switching positions with a unit?

Ruling: Azir's ability can be activated while he is exhausted because exhausting is not a cost for his ability - only 1 green power is required. You must play Azir to the field before you can activate his ability.

Sequence:

• Play Azir from champion zone to the field
• On a later turn, when an opponent showdowns on your battlefield with a friendly unit guarding, you can recycle a rune to activate Azir's ability and switch positions

Nuances:

• Unlike exhaust abilities where exhausting is a cost to activate, Azir's ability only requires paying 1 green power, so exhausted status does not prevent activation
• Azir must be on the field (not in champion zone) before his ability can be used