Wut Wuz Yers

Ok boss da cannon is rollin’ in now! Look at dem gits pullin’ it! Boggrub is gunna be happy wif ‘is Leadbelcher! Wutcha mean boom powder? Youse ain’t sed anyfing about boom powder in da Marshes! Course no git wuz gunna roll barrels o’ boom powder if no one sez to roll em! You roll barrels just cuz it’s fun?! No boom powder, no lead-belchin’, I knows. Youse in luck thou boss! Dem stunties in da stunty port has lotsa boom powder! Sum not far from ‘ere outside da port. We don’t have to go back to da Marshes when we’z got boom powder ‘ere!

Unfortunately you didn’t specify to bring the blackpowder with the cannon, so the blackpowder didn’t make the trip and is currently absorbing moisture in the Marshes of Madness. Luckily for you there is no shortage of blackpowder in Barak Varr. Kill the dwarf engineer at Burn Rock Tower and steal a Blastin’ Barrel.