Hi,
Each product can be linked to several categories.
So instead of :
main product category
- category 1
- sub category 1
- sub category 2
- category 2
- sub category 3
- sub category 4
You could have:
main product category
- shop by manufacturer
- category 1
- sub category 1
- sub category 2
- category 2
- sub category 3
- sub category 4
- shop by type of game
- category 3
- sub category 5
- sub category 6
- category 4
- sub category 7
- sub category 8
And thus, instead of one menu item with its main category being "main category", you could have two menu items, one with its "main category" being "shop by manufacturer" ( which would display the same thing), and one with its "main category" being "shop by type of game" which would list the products by type of game.
Then, in your products instead of having only one category in the "categories" setting, you could have two or more categories so that each product could appear for his manufacturer AND for one or several type of game categories.