Considering polite requests and firm demands to cease the use of the stolen materials have failed, he's touting it around on a page on Facebook, using almost a half-dozen known alts on that page, pretending each alt is a different person (all of whom conveniently agree with and defend him), calling out the page moderators and admins for continually demanding he stop using the stolen materials, becoming extremely defensive and harsh when said mods/admins are left with no choice but to use threats of page bans and content removal to try and get him to comply, parading the project around on various other sites including but not limited to the Chapel, Youtube, and his own personal page, and publicly and outright refusing to stop using stolen content and saying straight-up he will not credit or mention the original owner for its infringing use, and justifying such acts with clear-cut bullshit as "it can't be removed from the game" (hint, yeah it fucking can), I don't think we're being too aggressive here.
Hell, if I'm being honest, I don't think we're being aggressive enough. He's obviously not going to be swayed with reason (in fact he's made it abundantly clear he can't be reasoned with) or rationale discourse, and he has openly challenged the original owner of the stolen content over the matter. Personally, I wouldn't be against getting a whole troupe of people to follow him everywhere he posts the game and leave comments over what he's done and downvote the shit out of it all until he gets the damn memo and stops being a bastard. The project looked interesting enough to give a shot when first I saw it, but the actions and frankly infantile behavior of its creator has guaranteed I will not play it as long as he keeps this shit up; and I know for a fact I'm not the only person who feels this way.
So while I can understand the sentiment you're getting at of "two wrongs don't make a right," in some cases the only thing one can do is fight fire with fire. And if Ericard's continuous infringing and willful theft of an artistic work is anything to go by, that's the only option we have left if we want justice served. Obviously we can drop it and move on, but that's an even worse way to handle it as it basically tells Ericard this kind of behavior is tolerable and he can get away with it if he bitches and moans long enough. Sorry, I'm normally one to let bygones be bygones and move the fuck on with life, but this is an exception.
Ericard needs to have it bashed into his erroneously thick skull that this kind of shit isn't okay.