While this fan theory seems to have some evidence in its favor, it does leave a gaping plot hole. Namely, if Rick C-137 is the one who dropped a bomb on his family, why is he hunting Rick Prime for revenge? After all, if Rick Prime didn't slaughter Rick C-137's family, why is our Rick so dead-set on pursuing him to the ends of the universe?
If Rick C-137 killed his own family, a couple of things would still explain his vendetta. First, Rick Prime may still have been involved somehow, creating the scenario that led to the bomb being dropped through the portal, even if our Rick was the one who caused it to happen. Another possibility is that Rick C-137 blames Rick Prime for his family tragedy on account of him being the one to have given Rick C-137 the portal tech that led to the bombing. Rick has never been able to bear the blame for his mistakes, after all.
Whatever the reality of the situation, it's likely to be revealed when "Rick and Morty" returns for Season 7. The first episode of Season 6 dealt with Rick's vendetta against Rick Prime, while the finale implied that Season 7 will feature Rick and Morty teaming up to hunt him down. However, "Rick and Morty" loves nothing more than pulling the rug out from under its fans, so perhaps this macabre theory will remain just that.
