Faces invisible, what is wrong here?

[Murokmakto]

Hello,

So I have just finished my first go at asset creation. After trying to figure out blender and working on it for quite a while, I imported it into the game. It kind of works, but some faces are invisible. What is wrong here?
In Blender, these faces are in no way different than any other faces of the object. I carefully aligned them all to the uv unwrapped texture. However they are still missing. I am a very beginner, this is my first asset, so I might miss something here...
I apreciate the help, I can´t figure it out myself so far...

 

[Avanya]

The faces are turned the wrong way. You should be able to fix this in Blender fairly easily. Select all the faces in edit mode and select Recalculate Normals. That should have them all facing outwards like they should.

 

[Murokmakto]

Ok I will try that. Thanks cap!