Here, correct card rulings and highlight consistency points can be noted here and how there can be differences in Organized play.
Do note, nothing here is an official ruling, unless there's an official link from KDE (TCG or OCG), but the information here is correct and can be backed up by several sources.
*Important Note: A Fast Effect is a card and/or effect activation with a Spell Speed of 2 or higher.*
Scenario:
Player A controls 2 "Trickstar Reincarnation" & possesses 1 "Droll & Lock Bird" in their hand. Player B is the Turn Player. After drawing for their turn in the Draw Phase, BOTH PLAYERS AGREE to enter the Standby Phase ("Droll & Lock Bird" cannot activate its effect during the Draw Phase, so I am stating the Standby Phase for the relevance of its effect). No action is triggered by Player B entering their Standby Phase and Player B does not have a Fast Effect they can use. Due to this, the opponent, Player A, CAN activate their available Fast Effects in "Droll & Lock Bird" & their 2 "Trickstar Reincarnation".
Player A activates 1 of their "Trickstar Reincarnation". Their opponent has no response. The Chain resolves with Player B banishing all the cards in their hand, then drawing cards equal to the number banished by the effect of "Trickstar Reincarnation". Now, we follow the FET (Fast Effect Timing). Any effects Triggered by this action now occur (Example: "Thunder Dragonroar"). We follow the rules of SEGOC (Simultaneous Effects Go on Chain) and we place effects on our Chain in order, following SEGOC's structure.
1. TP Mandatory Trigger Effects
2. OP Mandatory Trigger Effects
3. TP Optional Trigger Effects
4. OP Optional Trigger Effects
I won't dive into SEGOC though, as the relevancy in this scenario is "Droll & Lock Bird" & "Trickstar Reincarnation". Information about SEGOC can be found in the basic rule-book and credible sources like YGOrganization. We'll assume no effects are triggered by Player B banishing or drawing cards. Now we follow the FET Chart, again. No actions that started a Chain occurred after "Trickstar Reincarnation" resolved. Therefore we move to Box B (Turn Player can activate a Fast Effect). The Turn Player is entitled to activate a Fast Effect (ex: "D.D. Crow"). However, we'll assume they don't have an effect ("D.D. Crow" wouldn't make a difference for what is about to happen.) If Player B doesn't have a Fast Effect they can/want to use, Player A is entitled to activate a Fast Effect (Box C).
Player A still has 1 "Droll & Lock Bird" in their hand and 1 Set "Trickstar Reincarnation". Now that Box B has been checked and we've entered Box C, Player A can (and will) activate their last Set "Trickstar Reincarnation". Is it important to note this action is occurring directly after the resolution of the previous Chain. So immediately after the first "Trickstar Reincarnation" successfully resolves, this second "Trickstar Reincarnation" is being activated. Player B can then respond with an effect with a Spell Speed that is equal to higher than "Trickstar Reincarnation" (Spell Speed 2). If they choose to do so (Ex: "D.D. Crow"), we follow basic Chain Rules (which can be found in the basic Rulebook). Even if "D.D. Crow" is Chained, Player A can still activate the Quick Effect of "Droll & Lock Bird" in response. Though the last action taken was the activated effect of "D.D. Crow", "Droll & Lock Bird" can activate given the word "If" in its text. "If" implies the activated effect won't miss its opportunity to activate when the last action to occur wasn't its activation requirement. Also, if "D.D. Crow" is NOT activated by Player B, then "Droll & Lock Bird" can still activate. Not only due to the reason stated above and these actions occurring directly after the previous Chain's resolution, but notably it is a Fast Effect. Since it's a Fast Effect and we've established "If", its effect can be activated either AFTER the activation of the second "Trickstar Reincarnation" currently on the Chain (or before if "Droll & Lock Bird" would've been activated before "Trickstar Reincarnation".)
Now for the Chain's resolution (we're going to include "D.D. Crow" in this Chain). Chain Link 3 resolves with the effect of "Droll & Lock Bird". Chain Link 2 resolves with "D.D. Crow" banishing the "Trickstar Reincarnation" in Player A's GY. Chain Link 1 resolves with "Trickstar Reincarnation". The effect of "Droll & Lock Bird" is applying, so how does "Trickstar Reincarnation" resolve? "Trickstar Reincarnation" was legally activated, before the effect of "Droll & Lock Bird" applied. While the effect "Droll & Lock Bird" is applying, the effect of "Trickstar Reincarnation" to banish cards in the opponent's hand and to draw cannot be activated. However as stated, the activation was legal. So what do we do? We resolve "Trickstar Reincarnation" as much as possible. We do the actions of its effect that are possible. Cards in the opponent's hand can be banished, so that will occur. Player B will banish all the cards in their hand. However they will NOT draw, since we cannot perform that part due to the effect of "Droll & Lock Bird". They will have 0 cards in hand. At this point, we've successfully completed "The Combo", stripping the opponent of potential effects they wanted to use during their turn.
This is a specific scenario as the parentheses within it implied various outcomes. Different cards and different effects could alter how the Chain resolves and what could occur ("Ash Blossom & Joyous Spring", "Called by the Grave", PSY-Framegear Gamma etc.). This is just to give an example of how the "Trickstar Reincarnation" and "Droll & Lock Bird" combo works in-depth using proper gameplay terms and sources (even if it was long.)
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Ok, so if you're somehow still here, then here comes another scenario involving "Droll & Lock Bird", except MUCH shorter. Instead it involves "Sky Striker Mobilize - Engage!".
Scenario:
Player A activates "Sky Striker Mobilize - Engage!" (while they have 3 Spells in their GY) and adds "Sky Striker Mecha - Hornet Drones" (it doesn't matter what "Sky Striker" card they add). Then, they choose to draw 1 card. After the ENTIRE effect of "Sky Striker Mobilize - Engage!" resolves, that is when "Droll & Lock Bird" can be chained. If Player A has 3 or more Spells in their GY when activating "Sky Striker Mobilize - Engage!, they will add, then draw. Only after the draw can "Droll & Lock Bird" can be used. If they don't have 3 or more Spells, then Player B can still (and will) use "Droll & Lock Bird" after the effect of "Sky Striker Mobilize - Engage!" has resolved and a "Sky Striker" card has been added by the opponent.
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Lastly "Droll & Lock Bird" cannot be activated during the Damage Step. Why? The effect of "Droll & Lock Bird" cannot be activated during the Damage Step cannot be used during the Damage Step, because it doesn't meet the criteria for effects that can activate during the Damage Step.
Damage Step Criteria:
● Counter Trap Cards.
● Mandatory Effects.
● Fast Effects that directly alter ATK/DEF. (Note: These can only be used activated during the Start of the Damage Step and Before Damage Calculation).
● Fast Effects that negate the activation of an action.
● Trigger Effects that activate when the card itself is moved in some way.
● Cards whose text specify an action specific to the Damage Step.
● Cards whose text say they can be activated during the Damage Step.
● Cards who have rulings that state they can be activated during the Damage Step.
For more information on the Damage Step, see:
http://www.yugioh-card.com/uk/gameplay/damage.html
Scenario:
Player A controls a face-up "Borrelsword Dragon". Player B controls a Set "Thunder Dragonmatrix". Player A declares an attack with "Borrelsword Dragon", selecting Player B's "Thunder Dragonmatrix" as the target. At the End of the Damage Step, after "Thunder Dragonmatrix" has been sent to the GY, its effect activates, adding 1 "Thunder Dragonmatrix" from the Deck to the hand. Player A cannot activate "Droll & Lock Bird" from their hand, since its effect doesn't meet the Damage Step Criteria, stated above.
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Nothing else I can give revolving "Droll & Lock Bird". Not every scenario can be accounted for, but obvious substitutions and applications can be done, depending on context. Hope you enjoyed reading this, though this should be simple to anyone who understands rulings on an above average level or simply plays this game enough to encounter such interaction. With that said, goodbye!~ <3
