Does activating Darius's ability without Legion count as playing a card for Legion purposes on other units?

Ruling: Triggering abilities does not activate Legion. Legion only activates when you have played a main deck card.

Nuances:

• Legion is shorthand for "do this if you have played another main deck card this turn"
• Simply tapping Darius's ability without having played another card does not count as playing a card for Legion purposes