Cat decks are fun, which means they're not viable. I tend to run this with a Purple Nymph and 5 pillars (actually 3 pillars and 2 pends for EQ resistance) since you only need 6
per turn at most and tend to get plenty early because of the automulligan giving you pillars.
Sometimes I run it with a Boneyard over a Vulture because the AI will spend all its AoE on Skellies.
Since the deck is super weak to CC, the strongest version is probably with Arsenics and Bone Dragons, but again we run Cat decks for fun.