While it has not yet emerged in Alchemy, Standard currently has a seriously strong Dinosaur deck
Being evasive is pretty unique for a soul sister, but it only has 1 power, so thats not a huge deal
The 1-of-1 The One Ring and pristine Alpha Black Lotuses are the most valuable cards in history, consistently exceeding $2M$3M at auction
If the player guesses incorrectly, the attacking player is able to cast it for free - otherwise they can investigate to gain a clue token
It can be a mana rock, draw you cards and help you proliferate
The cards and mechanics also incorporate the use of a D20 dice very familiar to tabletop RPG gamers and mostly only used in MtG as life counters, whose results affect spells, decisions and outcomes