First, remember that granting an already-toxic creature toxic 1 from Karumonix means itll give an opponent a number of poison counters equal to its total toxic value, so Blightbelly Rat actually connects for two poison counters with Karumonix on the field
Once you have a good amount, you can use the alternate commander from the deck, Vihaan, Goldwaker to transform all those Treasures into 3/3 artifact creatures that are also outlaws, giving them all vigilance and haste, both giving your other outlaws a huge boost, and your newly animated Treasure tokens the ability to swing out on the same turn
These commanders also include many popular creature-type favorites including Vampires, Rogues, Zombies, Faeries, and more
This kind of hand disruption is generally a bit off theme for these kinds of deck, it is not what you are really about so while it is quite good it just isn't that enticing or effective