Fabien Vehlmann and Jason worked together to create Isle of 100,000 Graves but since Jason is the one who drew it in his usual simple anthropomorphic animal style the only real noticeable difference from a regular Jason book is the slightly (very slightly) less oblique humour. There’s a bit more snap to the dialogue which worked very well.
The story is about a girl who gets a message in a bottle with a map to treasure. She heads out there looking for her lost father on a pirate ship and gets a pirate to buddy up with her. The island isn’t actually a lost treasure spot but has a more nefarious purpose: training executioners. There’s good infiltration and cleverness and it’s a pretty excellent, cleanly drawn, funny little pirate comic.