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It is an old cheap sci fi movie that got forgotten. It was about a war in the future with cyborgs. The last standing city of humanity's survivors plan to use the city energy source to travel back through time to escape demise. But their first jump is in our time near a small desert town and they open a small hole to send some of their warriors to check and secure the site for the town's arrival. Some cyborgs also follow them to attempt to sabotage the whole thing. When the town people start dying they join forces with the people of the future to fight them off. At the end the battle is decided when the main hero points the energy beam of the city against the hordes of cyborgs and wins the war.