Robotz

The deep space exploration ship DARWIN 8 has been invaded by
hostile alien robots. As the last surviving crew member it is your
job to deal with the problem.

The robots are all armed with laser guns and each group has at
least one positronic generator from which they draw their power.

Your rifle will only stun the robots while there is still an
active generator on the screen, so destroy these first and then
you can kill the robots.
Complete each level as fast as you can to pick up the time bonus,
but be careful not to walk into walls or barriers as these have
been electrified and contact with them is fatal.