When can a Hidden card that draws 2 be played during the opponent's turn?

Ruling: Hidden cards gain "Reaction" starting the turn after they were hidden, allowing you to play them any time you have priority during the opponent's turn.

Sequence:

• Hide the card
• Wait until the turn after it was hidden
• Play it as a Reaction when you have priority

Nuances:

• You can react to spells, activated abilities, triggers, and during showdowns
• You cannot react to units or gear entering play (unless they have "When You Play Me" effects that create a chain)
• Battlefield effects that trigger (like drawing when holding) can be reacted to