Rulings
Q1: Does this card's Breeding Your Turn effect also prevent my Digimon from DNA digivolving or burst digivolving?
That's correct, such digivolutions are also not possible.
Q2: Does this card's 1st Breeding Your Turn effect allow my Tamers to digivolve using a "you may digivolve as if your Tamer is a level 3 Digimon" effect?
No, they can't be digivolved.
Q3: Does this card's 1st Breeding Your Turn effect allow my Tamers to digivolve using digivolution requirements for digivolving from Tamers?
Yes, they can be digivolved.
Q4: What does "further reduce it by 1 for each of this Digimon's digivolution cards" in this card's 2nd Breeding Your Turn effect mean, exactly?
This effect additionally increases the numerical value of the play cost reduction in "when a Royal Knight trait Digimon card would be played, you may reduce the play cost by 4" in this carad's 2nd Breeding Your Turn effect. For example, if this Digimon has 1 digivolution card, the numerical value of the play cost reduction will be 5.
Q5: Can I choose to not reveal the top card of my Digi-Egg deck and not place my Royal Knight trait Digimon as this Digimon's bottom digivolution cards for this card's Breeding Start of Your Main Phase?
No, you must perform as much of the processing as possible.
Q6: If multiple cards are placed as the bottom digivolution cards for this card's Start of Your Main Phase effect, what order are the cards placed?
The player that activated the effect chooses the order of the bottom digivolution cards that are placed. Note that the cards placed by this effect must be placed under any already placed digivolution cards.
Q7: When I use this card's Start of Your Main Phase effect to place a BT17-078 Omnimon ACE under this card as a digivolution card, is BT17-078 Omnimon ACE processed?
No, it isn't processed. {{Overflow|}} is processed when a card is sent from the area or from under a card to another area. In this case, {{Overflow|}} isn't processed because a card from the area is placed under another card.
Q8: Can the play cost of a Digimon with the Royal Knight trait be reduced due to the Your Turn effect of my opponent's BT13-007 King Drasil_7D6 if BT8-071 Psychemon is in play?
No, they can't be reduced. BT8-071 Psychemon's effect does not target Digimon, so even if your opponent's BT13-007 King Drasil_7D6 is in the breeding area, its effect to reduce play costs can't be activated.
Q9: Does using BT10-110 Seiken Meppa trigger this card's inherited effect to gain memory?
No, using and activating BT10-110 Seiken Meppa's Main effect does not cause a card to be "placed" in the Battle Area, so this card's inherited effect does not trigger.
Data Sources
Lv.- King Drasil_7D6 BT13-007 SR Mega | Unknown | 9000 [Breeding] [Your Turn] All of your Digimon can't digivolve. [Breeding] [Your Turn] [Once Per Turn] When a [Royal Knight] trait Digimon card would be played, you may reduce the play cost by 4. Further reduce it by 1 for each of this Digimon's digivolution cards. [Breeding] [Start of Your Main Phase] Reveal the top card of your Digi-Egg deck, then place that card and all of your [Royal Knight] trait Digimon as this Digimon's bottom digivolution cards. --- Inherited: [Breeding] [Your Turn] [Once Per Turn] When an Option card with the [Royal Knight] trait is placed in the battle area, gain 1 memory.
Lv.- King Drasil_7D6 BT13-007 SR Mega | Unknown | 9000 [Breeding] [Your Turn] All of your Digimon can't digivolve. [Breeding] [Your Turn] [Once Per Turn] When a [Royal Knight] trait Digimon card would be played, you may reduce the play cost by 4. Further reduce it by 1 for each of this Digimon's digivolution cards. [Breeding] [Start of Your Main Phase] Reveal the top card of your Digi-Egg deck, then place that card and all of your [Royal Knight] trait Digimon as this Digimon's bottom digivolution cards. --- Inherited: [Breeding] [Your Turn] [Once Per Turn] When an Option card with the [Royal Knight] trait is placed in the battle area, gain 1 memory.
- King Drasil_7D6 BT13-007 SR Mega | Unknown | 9000 [Breeding] [Your Turn] All of your Digimon can't digivolve. [Breeding] [Your Turn] [Once Per Turn] When a [Royal Knight] trait Digimon card would be played, you may reduce the play cost by 4. Further reduce it by 1 for each of this Digimon's digivolution cards. [Breeding] [Start of Your Main Phase] Reveal the top card of your Digi-Egg deck, then place that card and all of your [Royal Knight] trait Digimon as this Digimon's bottom digivolution cards. --- Inherited: [Breeding] [Your Turn] [Once Per Turn] When an Option card with the [Royal Knight] trait is placed in the battle area, gain 1 memory.
Lv.- イグドラシル_7D6 BT13-007 SR 究極体 | 不明 | 9000型 ［育成］【自分のターン】自分のデジモン全ては進化できない。 ［育成］【自分のターン】［ターンに1回］特徴に「ロイヤルナイツ」を持つデジモンカードを登場させるとき、支払う登場コスト-4できる。このデジモンの進化元1枚ごとにこのコスト軽減効果の数値-1。 ［育成］【自分のメインフェイズ開始時】自分のデジタマデッキの上から1枚をオープンし、そのカードと特徴に「ロイヤルナイツ」を持つ自分のデジモン全てをこのデジモンの進化元の下に置く。 --- Inherited: ［育成］【自分のターン】［ターンに1回］特徴に「ロイヤルナイツ」を持つオプションカードがバトルエリアに置かれたとき、メモリー+1。