B, Tap: You lose 1 life and draw a card
Thatll suspend a card, getting an extra counter on Rose, even if you dont have anything with time counters when they attacked
Furthermore, this card has Ward which means it cannot be targeted unless by a challenge, making it more durable
When Keith attempted to slip a card from his wristband to the disk, it set off the cheat-prevention alarm, indicating that the Disk would not accept any cards on the Disk aside legitimate ones within the Duel, though this appears to be a feature of all the Duel Disks used in the arc as a whole, as indicated by the rules shown in the back of Volume Four (Keith had no knowledge of this due to the Disk being developed after his Penalty Game.)
One is that it can disrupt the opponent's strategy if there's a card in their Graveyard that they want to be there, and throw a huge wrench in their strategy