Loop Hero is not a demanding CPU game, in fact, it is one of the games that people recommend for people with inferior processors. However, the game still needs to render Graphics, so, if we would still recommend you check the system requirements before playing.
However, the major cause of this issue is corruption. Your game files either went missing or got corrupted. This especially happens during the time of installation. Now, when your computer is trying to load that file, because it is not there, the game stops responding and it crashes.
As for the black screen issue, more often than not, it is nothing more than a glitch. This glitch should get resolved by just switching to another game and then opening yours. If that is not the case, then the onus is on the GPU and the drivers. Also, we can not forget about your antivirus or Windows Security, as they can forbid the game from launching. Whatever the case is, we got solutions, so, just go to the troubleshooting guide and get on with it.