Does Tryndamere score 1 or 2 points when he conquers a battlefield while defending (moved there via Ride the Wind in response to an opponent's attack)?

Ruling: Tryndamere scores 1 point. His ability only triggers "after an attack" which requires him to be attacking, not defending.

Nuances:

• Doing damage in Riftbound is never classified as attacking
• The phrase "after an attack" is specific to when Tryndamere is the attacker, not when he defends during combat