Planet of Twins

My Role Producer, Developer & Designer
Team Solo scaling
Status Playable Prototype · 1 Playtests
Platform PC
Engine Unity 6.3 · URP · C#
Timeline January 2026 – Present

Planet of Twins is an original single-player action-adventure game set in a stylized East-Asian fantasy world, inspired by Binary Land on the NES. You control two twins at once, Kai and Lyra, and they share a single life. The further apart they drift, the faster their shared health drains, so closeness is survival and separation is death. Every system in the game is built around that one bond.

In feel it sits somewhere between Brothers: A Tale of Two Sons and It Takes Two, with the combat of a character-action game. It is at indie-AA scale: a systems-complete vertical slice built across more than 23 cross-wired systems, now entering the content phase.

This is the project where every part of my background meets. I own the roadmap, run the sprints, do the playtesting, and track the KPIs end to end. I also build it: the systems below are ones I designed and wrote myself. I am the producer, the developer, and the player who cares about whether the game actually feels right.

Planet of Twins torii garden
Planet of Twins world at dusk
Planet of Twins sakura world
Planet of Twins pagodas and lanterns

A look at the game in motion:

How I Run It

  • Full production ownership: I define the scope, build the roadmap, plan every sprint, break down the tasks, and track milestones across the project.
  • Playtest-driven iteration: I ran a structured 13-player playtest, collected behavioural and qualitative data on player flow, ability comprehension, and pacing, identified 4 critical friction points, and designed a targeted fix for each before committing development time. Two playtest rounds are behind the current build.
  • Engineering discipline: one consistent cross-scene rulebook, interface-typed dependency injection, data-driven tuning in ScriptableObjects, one effects path, one time-scale arbiter, and pooled spawns. The systems layer is kept clean so the content phase does not turn into a bug farm.
  • Business case: I built a formal Business Case and investment pitch covering the unique mechanics, market positioning, MSP, and a roadmap toward a funded vertical slice.

    • The Core: One Player, Two Twins

    System I built
  • Dual-character control: One player moves both twins together, Kai on the dark-energy side and Lyra on the soul-light side, and switches which one is selected for abilities while the other mirrors the movement. I built the input layer, the selection system, and the mirrored-movement handling so two characters read as one connected unit.
  • Proximity-based shared health: Both twins draw from a single health pool, and the distance between them drains it on a tuned curve, full when close and gone when far apart. This is the tension the whole game runs on, so I built the distance calculation, the drain zones, and the upgrade-aware modifiers from the ground up.
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    Enemy AI: A Hybrid Brain Per Enemy

    System I designed and wrote
  • GOAP + Behaviour Tree + FSM: Each enemy archetype runs its own brain. A goal-oriented planner sits on top and decides what to do, then hands execution down to a behaviour tree or state machine over a shared blackboard. This is the system I am proudest of, and it is the clearest proof of how I think about problems.
  • An emergent enemy ecology: On top of the per-enemy brains I built shared systems for mood, social bonds between enemies, points of interest, perception memory, and a faction-energy resource. Enemies even fight each other through a clan-war behaviour when no twin is nearby. Every archetype is designed to attack a different facet of the bond, dragging the twins apart, linking their health against them, or hunting the rescuing soul.
  • Built on a reusable framework: The decision systems share a blackboard and a service locator, so the AI is decoupled and reusable rather than hard-wired to this one game. New enemies are data plus a brain, not new plumbing.
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    Story, World & Cinematics

  • The premise: The twins are torn apart when the villain inverts an ancient curse. Where it once bound twins together, the planet now pulls them apart, and the corrupted people around them become the enemies. The world is built warm, alive, and beautiful precisely so its corruption reads as grief. Defeated enemies were once neighbours, so their freed souls power the twins, and the kills are framed as loss rather than triumph.
  • I wrote the narrative and built the cinematics using Unity's Cinemachine across the key story beats, including an intro sequence that teaches the twin relationship through an in-world catastrophe instead of a tutorial prompt. The mechanics and the story grew from the same idea, so playing the game is the story.
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    Abilities & Powers

    Systems I built
  • The twins grow through nine data-driven skill trees, and each clan brings its own powers that feed both combat and puzzle-solving. Every ability below is a system I designed, wired, and tuned. A shared effects engine drives the visuals so one call plays the particle, the VFX-graph effect, and the sound together.
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    MeleeClose-range attack dispatched to whichever twin is selected.
    StunCrowd control to lock a target down and buy space.
    PossessionTurn a corrupted enemy's own power against the fight.
    EmpowerA buff that strengthens the twins mid-encounter.
    Accord StateBoth clan powers channelled together, the twins' shared-power state.
    SetsunaA global slow-motion and rewind time system, separate from soul-mode freeze.
    Accord SpiritsFreed spirits rally to fight alongside the twins.
    Soul ConvergenceThe freed souls of the fallen city channel their power into the twins and fight back through them. It takes their sacrifice to activate.

    The Rescue: Weaver's Gate

    System I built
  • Weaver's Gate, the rescue ability: When one twin falls, the other's soul tears free from its body, crosses the planet's crack, and fights to bring them back before a countdown runs out. I built the whole rescue state machine, the soul travel, and the failure conditions. It is the moment the proximity bond pays off under real pressure, and it is the emotional centrepiece of the game.
  • Character progression: Both twins gain abilities through the skill trees as the player progresses, which feed into both puzzle-solving and combat. The unlocks, the point bank, and the upgrade-aware tuning all run through systems I wrote.

    • In Active Development: Toward a Vertical Slice

  • Planet of Twins is a systems-complete prototype now entering the content phase, built as a fundable product rather than a demo. The development plan, roadmap, and expansion artefacts are being refreshed to match the current build, and will be published here as the game moves toward a funded vertical slice.