Dogfaced puffers and Porcupines almost always get along with no hostility at all, likewise the "other porcupine", the burrfish......many will rarely eat fish flesh, alive or in pieces, at all and insist on shrimp/crab and squid.
Some of the smaller puffers and the tobies, however, can be real holy terrors towards any relative, and should be maintained one per tank.