As a complete outsider on these weapons I will take a guess and since I was looking at war canoes it does appear that what could be a "from that region" craft with the curved bows marked and of catamaran form with warriors down each flank and the central planking or walkway with the chief navigator and captain/leader …. the concept needs a seascape and I think a few inches down the blade you have just that.. but out of frame... at the stern more warriors shown . a fully armed and manned war canoe is my suggestion...
The war canoe best fitting that description is shown below and may be Maori but it gets across my point.