Q1: Can I use this card's digivolution requirement to digivolve for a cost of 5 even when my Takuya Kanbara has more than 5 Hybrid trait cards under it?

Yes, it can digivolve.

Q2: If this card gains Piercing from another card's effect, then this card attacks and deletes an opponent's Digimon in battle, do I perform the security check for Piercing after this card's Your Turn effect activates?

Yes. After this card's Your Turn effect activates, then you perform the security check for Piercing. This card's Your Turn effect and Piercing trigger simultaneously, but the activated Piercing is processed immediately before the attack ends, therefore Security Attack +1 is first gained from this card's Your Turn effect, then you perform the security check for Piercing.

Q3: BT18-088 Takuya Kanbara & Koji Minamoto digivolved into this card, and the memory gauge moved to 1 on my opponent's side. Then, I used this card’s When Digivolving effect to attack and used this card's Your Turn effect to unsuspend it. Can I then use the End of Your Turn inherited effect on BT18-088 Takuya Kanbara & Koji Minamoto in this card's digivolution cards to attack a player?

Yes, it can attack. When digivolving into this card, the turn end conditions won't be met until all of the resulting processing has been resolved. In this case, this card's When Digivolving effect, Your Turn effect, and any effects triggered by them must first be resolved, and then the turn end conditions will be met. Then, the end of the turn timing will occur and BT18-088 Takuya Kanbara & Koji Minamoto's End of Your Turn effect will trigger.

Q4: If there are 3 colors in this card's digivolution cards, can I use this card's When Digivolving effect to choose and trash 3 digivolution cards from my opponent's Digimon, then choose and suspend 3 of their Digimon?

Yes. For each color in this Digimon's digivolution cards, you choose and trash 1 digivolution card from your opponent's Digimon and suspend 1 of their Digimon.

Q5: Does the digivolution requirement that this card digivolve from a Tamer mean the Tamer that becomes a digivolution card is treated as if it is a Digimon when digivolving?

No. Digivolve from the Tamer as such, and do not treat it as if it is a digivolving Digimon. "When digivolving" effects and "when a Digimon digivolves" effects don't trigger. Additionally, if a "Digimon can't digivolve" effect has activated, you can still digivolve from a Tamer with this digivolve requirement.

Q6: Do I perform a digivolution bonus draw even if I digivolve from a Tamer?

Yes, you do. A digivolution bonus draw is performed for any kind of digivolution.

Q7: If this card digivolves from a Tamer that was played this turn, can it attack this turn?

No, it can't. A card cannot attack on the turn it is played, even if it digivolves from a card placed on the field. It can only attack if it was not played that turn.

Q8: Is a Tamer card placed under a Digimon considered a digivolution card?

Yes, it is. If the Digimon leaves the field, that Tamer is trashed like normal digivolution cards.

Q9: Does a Digimon gain the security effects in the lower text of a Tamer card in its digivolution cards?

No, it does not.

Q10: Does a Digimon gain the inherited effects in the lower text of a Tamer card in its digivolution cards?

Yes, it does.