Fast Leveling in The Alters
Last Variable requires the base game and specifically continues from the ending where Jan Scientist stays on the planet -- if you haven't reached that ending yet, finish the base campaign first rather than jumping into the DLC expecting it to work from any save state.
This is a genuinely story-heavy, choice-driven survival game -- go in expecting your decisions about resource rationing, time allocation, and resolving disputes between Alters to meaningfully shape the narrative, not just your resource totals.
Since planetary threats (earthquakes, radiation waves) are confirmed to become more common as you progress through Last Variable, don't treat early expeditions as representative of the difficulty curve -- budget real preparation time for later, more dangerous phases.
See the full data: The Alters Getting Started