Can you play a reaction speed effect during your opponent's turn without them playing something (like at end of turn in Magic)?

Ruling: No, you cannot play reaction speed effects during your opponent's turn unless they are responding to something on the chain. Priority only passes during showdowns or when an ability/spell are used, not between phases.

Nuances:

• Playing a unit without an enter effect does not give your opponent a window to react, as units resolve immediately
• Playing a unit with an enter effect does give priority to the opponent
• This is different from Magic where instant speed effects can be played between phases or at end of turn