/usr/lib/x86_64-linux-gnu/libxgks.so is in libxgks-dev 2.6.1+dfsg.2-3.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libxgks.so.2.6
/usr/lib/x86_64-linux-gnu/libxgks.so.2.6