Lavinia, Foil to Conspiracy conveniently taps to add two colorless mana, which is enough to sacrifice Clue tokens, but you can only activate it during an opponents turn
A BGS 10 Black Label example of that card sold for a record $5,100 on eBay in September, according to trading card sales database Card Ladder
For me, the tipping point is in the card type creatures are just much better than sorceries, adding the utility of attacking and blocking, paying sacrifice and convoke costs and everything else you need a body for in Magic
As long as this creature is attacking, creatures can't block unless their controller pays for each of those creatures
I can see this card going absolutely insane in decks with a lot of enters-the-battlefield triggers based around creatures
This left most people at a loss about how to store and protect the cards and components of the game, especially as the playmat was an easily damaged folded page