Tengu format ruling
Crystal Seer

Card effect (current official text)FLIP: Excavate the top 2 cards of your Deck, then add 1 of them to your hand, then place the other on the bottom of your Deck.
Rulings
- If there are less than 2 cards in your deck when this effect resolves, nothing happens.
- This effect can't activate if 'Thunder King Rai-Oh' is applying.
- The cards aren't revealed to your opponent (on Duelingbook, this can be resolved by drawing 2 cards, then placing 1 of the drawn cards on the bottom).
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.