One derivative vehicle, the Miura Next Heavy, would use two additional first stages as side boosters, analogous to the Falcon Heavy. In expendable mode it could place up to 36,000 kilograms into an ISS reference orbit, decreasing to 19,500 kilograms if the side boosters are landed back at the launch site.
A second derivative, Miura Next Super Heavy, would use four first stages as side boosters, arranged in a cross formation, an approach Torres likened to Russia’s Angara A5 launch vehicle. That would place 53,000 kilograms into an ISS reference orbit, or 13,660 kilograms into a Mars injection trajectory, in fully expendable mode.
They really went full Kerbal on that last one.
A quadruple booster landing would certainly be something to see, though I imagine it would be most efficient to stage them in pairs, landing two at a time.