Droll & Lock Bird

Per-phrase breakdown

• If a card(s) is added from the Main Deck to your opponent's hand, except during the Draw Phase (Quick Effect): You can send this card from your hand to the GY; for the rest of this turn, cards cannot be added from either player's Main Deck to the hand. (Quick)

Judge-facing facts

• Normal Summon / Set from hand uses no tributes (Level 1).
• This is a Quick Effect that activates in the hand.
• Sending this card from your hand to the GY is the cost to activate its effect.
• This effect cannot be activated during the Damage Step.
• If the opponent adds a card(s) from the Deck to their hand during a Chain's resolution, this effect can be activated in a new Chain after that Chain resolves.

Card-specific notes from database

• (YGOResources) While this effect is applying, cards that include drawing or adding a card from the Deck to the hand as a mandatory effect (e.g., 'Card Destruction', 'Trickstar Reincarnation', 'Stellarnova Alpha') cannot be activated.
• (YGOResources) If 'Droll & Lock Bird' is chained to 'Trickstar Reincarnation', the opponent's hand is banished but they do not draw.
• (YGOResources) Effects that draw cards when a condition is met (e.g., 'Maxx "C"', 'Multchummy' monsters, 'Shared Ride') can be activated while this effect is applying, but no cards are drawn when their conditions are met.
• (Konami neuron) Cards that optionally add a card from the Deck to the hand upon activation (e.g., 'Fire Formation - Tenki') can be activated while this effect is applying, but the effect to add a card cannot be applied.
• (Konami neuron) If the turn player adds a card to their hand and activates a Fast Effect as Chain Link 1 that prevents monster effects from being activated in response, the opponent cannot chain 'Droll & Lock Bird', and cannot activate it after that Chain resolves because the timing has passed.
• (Konami neuron) 'SPYRAL Double Helix' can be activated while this effect is applying; if the declared card type is excavated, you cannot add a monster from the Deck to the hand, so you must choose to add the 'SPYRAL' monster from the GY to the hand or Special Summon it.