In order to play SpaceChem well and solve puzzles efficiently the player should have a grasp of all the various gameplay components at their disposal, and be familiar with the associated rules. This page is designed as guide for learning and improving players. For those who are stuck and looking to progress further with the game, the Walkthrough page may be more appropriate.

Best Practices - reactionsEdit

  • Read the tutorials in the game, although bear in mind they do not always help directly.
  • Understand the functions and limitations of all the gameplay components, especially Waldos and Instructions.
  • Use Sync Instructions to eliminate collisions, and to compensate for delays caused by other instructions.
  • Use Sync Instructions just before a Waldo loops back to the Start Instruction - to ensure both Waldos run smoothly. As you improve your designs, this may not be required.
  • Wherever you Drop an atom or molecule into an Output area - there must follow an Out Instruction, in order to remove it.
  • Using fewer instructions and reactors, will result in more efficient solutions and improve your ranking.
  • Understand that there are limitations when bonding atoms, as certain atoms can only have a certain maximum number of bonds. Consult the Periodic Table information.

Best Practices - multiple reactorsEdit

  • Read and understand the requirements and limitations in Production Assignments.
  • When dealing with assignments containing multiple reactors, it is helpful to use the notes section on the reactors output pipes to keep track of what molecules you are trying to create.
  • When dealing with assignments with multiple reactors, note the reactor grid square where you drop an output, atom or molecule. This is the corresponding grid square for the input of the next reactor.
  • Dropping a same atom type on 2 different output-grid-squares, this may sometimes be to your advantage.
  • In production assignments, the length of a pipe can be extended beyond what is needed to reach the next reactor in order to provide a buffer to help stop reactors from stalling due to being unable to complete an Out Instruction.
  • Any "In" or "Out" Instruction waits on the grid square until this command can be executed. Thus this is some kind of sync, when supply is slow from the previous reactor.
  • Try to do as much as possible with each Waldo, in order to save on needed reactors (reactor limit!).

Advanced TechniquesEdit

  • A Waldo running into a wall will constantly repeat the instruction under it.
  • Bonders have a hidden priority which determines which order bonds will form in. This priority stays the same even if the bonders are moved. This can be exploited to make more compact solutions.
  • The red Waldo always has priority over the blue Waldo and will complete its command first each cycle.
  • If you give a global instruction with the 2nd Waldo (+bond fuse etc) at the same time, you can execute 2 commands in 1 grid-square.
  • With a Fusion Reactor, you can get rid of unused Hydrogen by fusing it! This will work 109 times.