If Darius enters the battlefield as the second card of the turn, will he enter ready since the condition is already fulfilled?

Ruling: Yes, when Darius is played as the second card of the turn, his ability will trigger and ready him.

Nuances:

• If Darius is the third card played this turn, he will not ready himself because he is not the second card played and he was not on the board when the second card was played.