/usr/share/doc/grub-invaders/examples/grub-menu.lst is in grub-invaders 1.0.0-13.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 | # sample /boot/grub/menu.lst entry for grub-invaders
#
# This example assumes the contents of /boot is on the root partition.
# If your /boot is on its own partition, remove /boot from the 'kernel' line.
title GRUB Invaders
root (hd0,0)
kernel /boot/invaders.exec
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