While first-edition copies are difficult to come by, they're not as rare as the Neo Destiny Feraligatr, presenting more sales to analyze
Starting life as a 3/3 means Baron Helmut Zemo can get pretty intimidating very quickly even without activating Boast, but the Conniving can be strategically done to load your graveyard and activate Boast much quicker

45 Slowpoke [1st Edition] Team Rocket [1st Edition] 67 Slowpoke Delta Species 83 Slowpoke [1st Edition] Golden Sky, Silvery Ocean 40 Slowpoke Old Maid Slowpoke HeartGold Collection 17 Slowpoke Dark Explorers 23 Slowpoke HeartGold & SoulSilver 81 Slowpoke Stellar Crown 57 Sabrina's Slowpoke Gym Heroes 95 Slowpoke Unseen Forces 72 Slowpoke [Reverse Holo] Unbroken Bonds 42 Slowpoke [Reverse Holo] Guardians Rising 48 Slowpoke Super-Burst Impact 24 Slowpoke Full Metal Wall 11 Slowpoke Generations Starter Decks 27 Slowpoke Call of Legends 70 Slowpoke Legendary Collection 93 Slowpoke Guardians Rising 48 Slowpoke Team Rocket 67 Slowpoke Rocket Gang 32 Galarian Slowpoke Silver Lance 30 Galarian Slowpoke Single Strike Master 21 Slowpoke Pokmon Card 151 79 Galarian Slowpoke Start Deck 100 164 Slowpoke Unbroken Bonds 42 Slowpoke Mystery of the Fossils 27 Slowpoke Shiny Treasure ex 36 Recall Nivi City Gym Deck 71 Slowpoke Generations 32 Slowpoke BREAKpoint 19 Slowpoke [Master Ball] Prismatic Evolutions 18 Sabrina's Slowpoke Challenge from the Darkness 44 Slowpoke Fossil 55 Slowpoke Stellar Miracle 38 Slowpoke [Poke Ball] Prismatic Evolutions 18 Slowpoke [Reverse Holo] Hidden Fates 12 Slowpoke Snow Hazard 29 Slowpoke Violet ex 19 Slowpoke Pokmon GO 19 Slowpoke [Reverse Holo] Paldea Evolved 85

The CatOven combo is a great way to stabilize against more aggressive decks, especially when combined with Mayhem Devil and The Meathook Massacre
It can stand alone on its own and be a scalable mass removal, or a bank of energy to store for later in energy decks
Well, yeah, Ill concede that as a mono-color card its a lot fairer than if it had access to more colors