Q: What rights do I retain when I buy a game and a new parent company decides to enact something where I cant play anymore

A: Based on the information provided, you may have some consumer rights in this situation, but seeking recourse could be challenging:

- When you purchase a video game, you are typically purchasing a license to use the software, not outright ownership. The license agreement usually gives the company certain rights to make changes.

- However, there are consumer protection laws in California and at the federal level regarding digital content and software. Under California law, there may be an argument the mandatory migration constituted a "material change" that reduces the overall value, violating certain consumer rights.

- The challenge is, most video game license agreements require agreeing to binding individual arbitration to resolve disputes, rather than going through the court system. So your practical options to fight back alone are limited.

- Documenting your original purchase from 2010 would be important. Writing a complaint to Microsoft highlighting your long-time patronage and loss of access to legally purchased content may also be worthwhile. But there would likely need to be an organized, collective effort to push back effectively.

- Consulting a consumer protection attorney for additional advice would also be recommended to fully understand what rights you retain in this situation under California and federal law before taking any action. There may be additional options through the legal system, especially if more users come forward.

In summary - you may have some legitimate grievances based on your long-time purchase, but ability to exert those consumer rights against a major company is difficult without significant resources and collective action. But consulting an attorney in CA could help shed light on viable options.