Using a Modular Starship, many different configurations can be assembled in LEO for a range of mission profiles.
The above video is just one example. Send up a couple of Crew Pods, attach however many fully fueled tugs as needed, then off it goes.
No lander was attached as this would be for a transfer or flyby mission only. A Mars Lander pod could be attached as well for destination missions.
Even more tugs could be attached as needed for the mass of the configuration.
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