Grand Commander

Whoa there, space cowboy! There’s zombie aliens in them hills. Are you up to the challenge of running them out of town? Kill as many zombies as you can for as long as you can to prove yourself worthy of the title “Grand Commander.” How many of the undead scum of the universe can you send back to where they belong?

Fight the hordes of zombie aliens that have overrun this frontier town in space.
Use power ups to clear off large hordes of zombie aliens at once.
Keep fighting for as long as you can.

This extension provides additional games,