Among modern cards (20222026 releases), Mega Charizard X ex SAR from Inferno X leads at 122,000 ($767) in PSA 10
Groudon One of the best art rares in the set and a strong binder card
Some of the cards from the set were actually decent, but they had a functionality that would work better in a Sealed Deck or Draft format
Whether these inflated prices will hold remains to be seen, but considering the events month-long duration and no indication from TPC or McDonalds that supply shortages are expected, its unlikely that these mark-ups will hold
Rather than paying six mana for Sanctuary Warden (which is still a fine card for these decks) you should first be taking Angelic Sleuth
When this card inflicts Battle Damage to your opponent by a direct attack, remove from play all Synchro Monsters in your opponent's Graveyard, and inflict 1000 damage to your opponent for each monster removed.