You want a 3 slot one. I look for the lowest Intel possible. So you can get more Strength. But any will work for using on a ship.
I wish I could find the one I made in that thread linked above. It could be the one that fell off my ship one day and I never saw it again.
Also made another info thread on them.
The sea creatures you encounter when looking for Pirates or Beacons are not difficult for a pet to kill.
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