Does Darius Trifarian get +2 Might if he's already readied at the start of your turn when you play two cards, or does he need to be readied by his ability to get the buff?

Ruling: Darius Trifarian gets the +2 Might bonus even if he's already readied. The ability still attempts to ready him (which has no effect if already ready), but the Might buff applies regardless.

Nuances:

• Darius himself counts as the second card if you play him after playing another card
• The ability triggers on your opponent's turn if you play 2 cards, granting the Might buff, but Darius cannot move since it's not your turn