This is really overkill for a game but I can't really suggest much (detached handle example) without knowing the type of game and how you wanted to use the mug but as it stands I'd argue it's even overkill for a movie prop If it's a hero object in a first person game (like a gun in call of duty) then you want higher poly…
Game engines work with triangles not quads/polys and automatically convert a quad mesh when it's imported, explained properly in Chad's link above (again look at any games mesh like the one I shared), you generally want quads for subdiv modelling and I guess some editing tools work better (blenders loop cut CTRL + R only…
As said above, good texturing with PBR materials, good lighting and 2dfx (like the smoke) and well optimised models. Here's a good quick example of high poly to low poly baked material use Source: https://www.reddit.com/r/blender/comments/1sgac0v/this_is_your_sign_to_learn_how_to_bake_normal_maps/ Or better yet here's a…
Agreed with Flat Face. Definitely think about the context that you envision for this asset. Think about how much screen space it will take up and how the player will interact with it. e.g. will it take up the whole screen and will the player get to visually analyse it for as long as they want? or will it be a small prop…