- The Alters Last Variable expansion how to play: Access the DLC via the "New Game" menu; it functions as a separate 20-hour campaign.
- Core Objective: Survive 13-year hot phases by building a Cryosleep Chamber within a strict 14-day deadline.
- Specialist Alters: Create Geologist, Physicist, Chemist, and Biologist versions of Jan to automate resource extraction and research.
- Terraforming: Deploy three tiers of Terraformers across 9 arenas to stabilize the planet's environment.
- Ending Choices: The final branch depends on your response to JanBot regarding the succession of the Oasis project.
DLC Access and Initial Setup
Starting the expansion requires owning the base game, but the campaign itself is a standalone experience that follows the timeline where Jan Scientist remains on the planet. To begin, navigate to the main menu and select "Start New Game," then choose the Last Variable route. This campaign introduces an underground base structure, distinct from the mobile base in the original game, requiring a fresh approach to logistics and resource management.
Video Highlights:
- DLC Entry: How to launch the expansion from the main menu without a base-game save.
- Underground Layout: Overview of the new soil-based construction mechanics.
- First Tasks: Immediate steps to repair the Research Lab and meet JanBot.
| Feature | Requirement | Details |
|---|---|---|
| Base Game | Required | Must own The Alters to play Last Variable |
| Platform | PC, PS5, Xbox | Available on Steam, Epic, GOG, and consoles |
| Playtime | ~20 Hours | Includes main story and optional Alter quests |
| Price | $14.99 | Standard price for the standalone expansion |
| Saves | Separate | Does not carry over base game inventory or structures |
While you can play the expansion immediately, it is highly recommended to finish the original campaign first. The narrative heavily references the emotional weight of Jan Scientist's decision to stay behind and his complex relationship with the other Jans.
Cycle 1: The 14-Day Survival Deadline
The most critical aspect of The Alters Last Variable expansion how to play is managing the opening 14 days. You are tasked with the "Forced Dormancy" objective, which requires the construction of a Cryosleep Chamber. Failure to complete this before the planetary hot phase begins results in a game over. Your initial focus must be split between immediate repairs and establishing a sustainable Metal and Rapidium income.
Repair the Research Core
Locate the damaged Research Lab and use 10 Metals to craft a Repair Kit. This unlocks the ability to research the New Branching Procedure, which is essential for creating your first specialist Alter.
Establish Resource Outposts
Travel south of the base to find Metal and Rapidium deposits. Build automated outposts immediately. Manual gathering is too slow to meet the 14-day construction requirements for the Cryosleep Chamber.
Create your First Alter
Use the Quantum Computer to create an Alter. For Cycle 1, the Jan Geologist is the optimal choice to boost Metal mining efficiency by 50%, allowing for faster base expansion.
The Oasis Investigation
Enter the Oasis biome to collect three Electric Algae samples. Use these at the Lab to research Phased Rapidium, a material required for both the Cryosleep Chamber and the first Terraformer.
Never let your Metal reserve drop below 10. You always need enough for an emergency Repair Kit in case an earthquake damages your power supply or life support modules.
Specialist Alters and Work Assignments
Success in the expansion depends on how you utilize the four new Specialist Alters. Each specialist provides a massive boost to specific research projects and base operations. Unlike the base game, these Alters are often assigned to Field Labs—remote research stations where they work independently for entire cycles.
Jan Geologist (Priority: S)
- Specialty: Geology, mining, and terrain barriers.
- Bonus: 50% faster Metal extraction.
- Best Use: Early-game resource gathering and clearing root barriers.
Jan Physicist (Priority: A)
- Specialty: Advanced instruments and power systems.
- Bonus: 50% faster Workshop crafting.
- Best Use: Producing high-tier components like Resistor Blocks and Splitters.
Jan Chemist (Priority: A)
- Specialty: Refined materials and Field Lab research.
- Bonus: Completes Field Lab projects 40% faster.
- Best Use: Assigning to remote labs to unlock Megafluid and Proxylium.
Jan Biologist (Priority: B)
- Specialty: Greenhouse, medical, and Oasis samples.
- Bonus: 100% faster crop growth and 8x faster healing.
- Best Use: Maintaining crew morale and health during long cycles.
| Specialist | Key Research Contribution | Personality Trait |
|---|---|---|
| Geologist | Phased Rapidium, Anomaly Repulsor | Adventurous, supports exploration |
| Physicist | Splitter, Magnetometer, Mass Spectrometer | Status-conscious, needs recognition |
| Chemist | Proxylium, Megafluid processing | Pragmatic, values efficient plans |
| Biologist | Terraformer Tier II/III, Slime usage | Idealistic, needs visible progress |
Before sending an Alter to a Field Lab, finish their personal conversation events. Once they are at a remote station, they cannot participate in base social events, which might stall their relationship progression.
Terraforming Arenas and Resource Routes
The map consists of nine distinct arenas. Except for the Oasis, every region must be terraformed using one of three Terraformer tiers. Each successful transformation changes the landscape, opening new paths to rare resources and Field Lab sites.
| Arena | Terraformer Tier | Key Resources | Field Lab Access |
|---|---|---|---|
| Oasis | None (Reference) | Electric Algae | No |
| Rocky Valley | Tier I | Metals, Obsidian | Yes (Lab 1) |
| Base Arena | Tier I | Organics, Debris | No |
| Misty Gorge | Tier II | Enriched Metal, Polymer Gas | Yes (Lab 2) |
| Volcano | Tier II | Minerals, Obsidian | No |
| Far Hill | Tier III | Mushrooms, Megafluid | Yes (Lab 3) |
To progress the "how to play" loop, you must balance the energy cost of Terraformers with the base's power capacity. Tier III Terraformers require Megafluid, which can only be produced after completing research in at least two Field Labs.
Terraforming triggers planetary reactions. Expect increased radiation waves and earthquakes immediately following a successful transformation. Ensure your Radiation Filters are stocked before activating a new Terraformer.
Underground Base and Cryosleep Logistics
The underground base is static, meaning you must plan your layout carefully around soil restrictions. Some cells are comprised of hard rock that requires advanced drilling research to clear. Efficient placement of the Workshop and Storage near the elevator will minimize travel time for Jan and the Alters.
Final Day Cryosleep Checklist:
- Reserve 50 Organics for every person entering the chamber.
- Assign a specialist to a Field Lab to continue remote research.
- Dismantle surface extractors to recover parts before the hot phase.
- Heal all crew members to 100% to avoid 'Waking Trauma' debuffs.
- Complete all pending research projects in the Lab.
| Module | Cost (Metals/Rapidium) | Function |
|---|---|---|
| Cryosleep Chamber | 50 / 65 | Required to end the cycle |
| Sample Analysis | 60 / 50 | Processes Oasis evidence |
| Splitter | 300 / 0 | Refines advanced materials |
| Proxilium Tank | 150 / 0 | Stores mid-game rare gases |
If you lack the 50 Organics per person required for cryosleep, you will be forced to leave an Alter behind or face a critical failure. Always prioritize the Greenhouse or Organics Outposts during the final three days of a cycle.
Endings and Achievement Guide
The expansion concludes with a final confrontation regarding the "Last Variable"—the ultimate nature of the Oasis. There are two primary endings, determined by your final interaction with JanBot after activating the ENC Generator.
Ending Paths:
- Create a Successor: Jan chooses to perpetuate the cycle of scientific obsession, ensuring the research continues beyond his own life through a new Alter.
- Break the Cycle: Jan accepts the limits of human knowledge and refuses to create another life to carry the burden of the Oasis, effectively ending the experiment.
Q: How do I play the expansion if I haven't finished the base game?
You can select 'Last Variable' from the New Game menu. The game provides a brief summary of why Jan Scientist is alone on the planet, though playing the base game first is recommended for context.
Q: Can I create the same specialist Alter twice?
Yes. In fact, doing so unlocks the 'Wait, you can do that?' achievement. This is useful if your original specialist is stationed in a Field Lab and you need their bonus back at the base.
Q: What is the most important resource in the late game?
Megafluid and Phased Rapidium are the primary bottlenecks for Tier III Terraformers and the final ENC Generator components.
Q: How do I unlock the 'Caring after all' achievement?
You must complete the individual personal questlines for all four specialist Alters (Geologist, Physicist, Chemist, and Biologist) before activating the final generator.
The game creates an autosave right before the final conversation with JanBot. You can use this save to view both endings without replaying the entire 20-hour campaign.