Card Rulings:Morphing Jar
- The monster effect of "Morphing Jar" is a Trigger Effect that always activates when it is flipped face-up. (It activates even during the Damage Step.)
- The application of "Both players discard their entire hands" and the application of "draw 5 cards" are not treated as being done at the same time. (Discarding the player's hand is treated as being done at the same time as discarding the opponent's hand. Also, the player drawing 5 cards is treated as being done at the same time as the opponent drawing 5 cards.)
- When resolving the effect of "Morphing Jar", even if either player (or both players) has no cards in their hand, it is still possible to draw 5 cards from the Deck.
- A: If the player and the opponent collect all five pieces of "Exodia the Forbidden One" ("Left Leg of the Forbidden One" etc.) in their own hands at the same time, the Duel is a "DRAW".
- A: If adding Rock-Type monsters from your Deck to the hand by the effect of "Block Dragon", choose 1-3 Rock-Type monsters so that the total Levels of the chosen Rock-Type monsters is exactly 8. For example, you can apply the effect by adding only 1 monster: a Level 8 "Block Dragon"; or by adding a total of 3 monsters: 1 Level 2 "Morphing Jar", 1 Level 2 "Medusa Worm", and 1 Level 4 "Blockman".
- Q: The monster effect "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" of "Digital Bug Scaradiator" was activated by targeting a face-up Defense Position "Morphing Jar" in the opponent's Monster Zone. If "Book of Moon" is activated in chain to that activation and "Morphing Jar" changes to face-down Defense Position, how does it resolve?
- A: In this scenario, even if the "Morphing Jar" targeted by the monster effect of "Digital Bug Scaradiator" is in face-down Defense Position when the effect resolves due to a "Book of Moon" activated in chain, the effect is still applied as normal. In this case, the currently face-down Defense Position "Morphing Jar" is changed to face-up Attack Position, and the effect "it has its effects negated until the end of this turn" is applied. (The monster effect "FLIP: Both players discard their entire hands, then draw 5 cards" of "Morphing Jar" is activated and makes a Chain Link, but that effect is negated and is not applied.)
Upper Deck Entertainment Rulings
These TCG rulings were issued by Upper Deck Entertainment and have since been declared unofficial by Konami. They were previously considered official and can still be correct, as long as they follow the official gameplay rules, or unless Konami has issued a ruling that says otherwise. References: 
- Morphing Jar
- Konami OCG Card Database: Ruling #11357
- Konami OCG Card Database: Ruling #18902
- Konami OCG Card Database: Ruling #18157
- Konami Judge Program Forum: Individual Email Rulings VS Individual Card Rulings
- UDE FAQ: Individual Card Rulings [A-C]
- UDE FAQ: Individual Card Rulings [D-E]
- UDE FAQ: Individual Card Rulings [F-H]
- UDE FAQ: Individual Card Rulings [I-K]
- UDE FAQ: Individual Card Rulings [L-O]
- UDE FAQ: Individual Card Rulings [P-R]
- UDE FAQ: Individual Card Rulings [S-T]
- UDE FAQ: Individual Card Rulings [U-Z]
- UDE FAQ: SPECIFIC CARDS RULINGS