THESE NINJUTSU ABILITIES ARE GETTING OUT OF HAND
A deck that uses Pitiless Plunderer only needs to sacrifice a token creature or use one as a chump blocker, and thats just the first synergy that comes to mind
The problem with Cavern of Souls is that a playset is almost $140, which means if we simply switched Cavern for some more Plains, Cats would basically be a Budget Magic deck
They usually look unofficial, with plain paper, office-printer layouts, black-and-white text, sometimes even handwritten notes, because they were never meant to be sold or packed into boosters
Especially Misty and Professors Research are candidates that are more likely to be played early
Treasures and Tricks with Prosper, Tome-Bound Next, we have Prosper, Tome-Bound who is a Red/Black scary looking Warlock