I've raised a curupira with cichla and with bichirs, but idk if I would be willing to try with pikes if you aren't willing to risk them. They're so similar in shape, and both species can be boisterous....it's definitely a risk but could work. For it to work, you want your curupira to be the smallest fish in the tank, make sure that you have plenty of space. Also make sure that the wolf eats his fill.