OCG Card Database Rulings Reference: https://www.db.yugioh-card.com/yugiohdb/faq_search.action?ope=4&cid=4597&request_locale=ja
① FLIP: Both players discard their entire hands, then draw 5 cards.
Rulings:
①: The monster effect of "Morphing Jar" is a Trigger Effect that activates whenever it is flipped face-up.
(It can also activate during the Damage Step.)
■ The effect does NOT target.
■ The actions of "Both players discard their entire hands" and "draw 5 cards" do NOT occur simultaneously. (The process of you and your opponent discarding your entire hands is performed at the same time.) (The process of you and your opponent drawing cards is performed at the same time.)
■ When resolving the effect of "Morphing Jar", if either player or both players have 0 cards in their hand, you still draw 5 cards from the Deck.
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*Translations aren't 100% exact, but the translation is still accurate.*
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Question:
If 5 cards are drawn by the effect of "Morphing Jar" etc. , such as "Exodia the Forbidden One" & "The Left Arm of the Forbidden One" etc. and they are placed in your hand and your opponent's hand simultaneously, who wins the Duel?
Answer:
If both players draw all five pieces of "Exodia the Forbidden One" from the effect of "Morphing Jar" etc., then the Duel ends in a DRAW.
Source: https://www.db.yugioh-card.com/yugiohdb/faq_search.action?ope=5&fid=11357&keyword=&tag=-1&request_locale=ja
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Question:
My opponent controls a face-up Defense Position "Morphing Jar". I activate the monster effect of "Digital Bug Scaradiator", "Once per turn, during either player's turn: You can detach 2 Xyz Materials from this card, then target 1 monster your opponent controls; change its battle position, and if you do, it has its effects negated until the end of this turn." What will happen when my opponent chains with their "Book of Moon", targeting their "Morphing Jar" and changing it to face-down Defense Position?
Answer:
In the scenario above, due to the effect of the "Book of Moon", that was chained to the monster effect of "Digital Bug Scaradiator" which targeted "Morphing Jar", will change "Morphing Jar" to face-down Defense Position when resolving, like usual. In this scenario, "Morphing Jar" will change from face-down Defense Position to face-up Attack Position and the effect "it has its effects negated until the end of this turn." will be applied. (The monster effect of "Morphing Jar", "FLIP: Both players discard their entire hands, then draw 5 cards.", will activate and start a Chain, but it will be negated and it will NOT be applied.)
Source:
https://www.db.yugioh-card.com/yugiohdb/faq_search.action?ope=5&fid=18157&keyword=&tag=-1
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*There's another database ruling for "Morphing Jar", but that ruling will be left out, because it doesn't have anything to do with the functionality of its effect. It instead is undercovering criteria for the card "Block Dragon".*
