This is the UZI, MAC-10 hybrid I made in blender. This ended up being the only fully rigged model because of time constraints. One of the only problems I ran into was during rigging where the magazine would do a 180 degree flip whenever I would add the copy rotation and location contraints like in the image below.
Before
How I fixed this is I simply added -180 degrees of rotation to it to flip it back around which removed the problem entirely.
After
A shotgun based on a SPAS-12 that I created. There is not much to say apart from the fact that I had problems with making the little ridges on the gun. There's another image to show that more clearly.
This is the final version but at first I tried to use stretched out cones at first for whatever reason. It was something like the image below, and I used the boolean modifier to attempt to indent it into the gun. This unfortunately did not look nice so I had to change it.
What ended up working is getting a cube, stretching it, loop cutting a few times and adding a curve modifier to it. All I had to do is adjust it but after some time I ended up with the nice ridges that are visible on the gun.
This is the starting area for the tutorial level. The biggest room is the jail cell when the player wakes up from and there are two corridors put in. What I planned out is that I would make a series of interconnecting rooms which I can just put together like Legos and therefore quickly make the levels. Unfortunately, I didn't have time to create them so this is all I have in terms of level design.