Allright, seems build runs ok for a while and does its core compilation until it meets
[3/5] Compile [x64] Valador_2.cpp, seems over there a compilation error.
If you make a another target to build we can get more info about the error also.
Try deleting the Intermediate folder, it can help sometimes
Generally when a c++ code compiles ok but creates problem in build is due to the code snippets that meant not to be in build. Like editor only decleration etc.
If its not big file you can paste and we can take a look, however you can search for code snippets that are editor only too.