The actual prohibition is that of doing Shirk or having shirk as a belief system. However, Movies or Games containing any such motivations or explicit references to Polytheistic Acts should be avoided on sadd-e-zariya principle as constantly watching these things can make a person very lenient about severity of these things and it may lead one to get involved into such acts himself one day, because of lower threshold developed in a person with constant watching such acts. But no fatwa of absolute prohibition can be given in this regard, because absolute prohibitions are very explicitly mentioned in Quran.

There is no such thing as minor Shirk. There is Shirk and then there are certain types of polytheistic attitudes (‘Shirkiya Rawaiya‘) that have a reflection of Polytheism or may lead to Polytheism if one is being careless. The former is prohibited while the latter is also something one should be very sensitive about.

Please understand the underlying principle that Ghamidi Sahab is trying to portray here:

https://youtu.be/xvsEasCPRBU

For details on What is Shirk and What are ‘Shirkiya Rawaiyai’, please refer to following lectures:

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