you need to execute BerserkSurvivor.x86_64
try opening the directory that you extracted the files in a terminal and executing
chmod +x BerserkSurvivor.x86_64
then try to open the BerserkSurvivor.x86_64 file
if it doesn't work, i couldn't find a solution (i couldn't open the game too), but is probably because file format incompatibility with your linux system