Several factors influence Diamond & Pearl card values: card condition (mint cards worth 3-5x more), rarity (holographic and rare cards command higher prices), first edition status, PSA/BGS grading scores, and market demand for specific Pokemon
To attack or use an ability, players must tap the card (turn it 90 degrees clockwise) to indicate its use (unless the card has vigilance )
Or, you know, one Akroma Angel of Wrath in the bin
Obelisk the Tormentor, Slifer the Sky Dragon, Ra the Winged God are all direct mythology pulls
Just drop down any creature with undying (the opposite ability that gives them +1/+1 counters instead), or a Mikaeus, the Unhallowed, and youve got an infinite sacrifice combo ready and raring to go