The Walktapus has Poison Gas Cloud 18w, but its poison gas has a potency of 20. Which is used?
The walktapus may use the PGC ability as an augmentation to it’s normal attacks. In this case, the “poison” is not lethal. If the narrator introduces a scenario where a hero is actually poisoned with Walktapus gas (fighting in an enclosed space or having a bag full of gas pressed to his face, for example) then the potency of the gas is used.