For a quick, placeholder tutorial, this is my suggestion:
The first time you click New Game, it takes you to the tutorial screen, which is a dark background with white text, with occasional pictures, reading:
On a distant alien planet, millions of years of meteor impacts and volcanism have led to the development of a new phenomenon in the universe… life. These simple microbes reside in the deep regions of the ocean, and have diversified into many species. You are one of the many species that have evolved.
To survive this hostile world, you must collect compounds from your environment and evolve each generation to compete against the other species of cells.
Controls
Change Orientation : Mouse cursor
Movement : WASD
Compounds
Compounds exist in coloured clouds in your environment. Move your cell over these clouds to absorb them (provided you have enough room in your cell to store it). (Insert picture of compound clouds).
The colour of the cloud identifies which compound it is. The different compounds are:
White – Glucose
Pinkish Red – Amino Acids
Dark Red – Proteins
Yellow – Ammonia
Light Blue – Oxygen
Dark Blue – Carbon Dioxide
Gameplay
ATP is the energy of your cell. (Insert picture of ATP display on UI). ATP is used by your cell to move and to stay alive. However, you cannot find ATP in the environment. ATP must be harvested from compounds in your environment.
Every cell is composed of cytoplasm. Cytoplasm allows a cell to turn glucose into ATP (in a process called Glycolysis), so absorbing glucose clouds a common way for most species to make ATP. Cytoplasm also serves as storage for compounds you collect.
Mitochondria can produce much more ATP from glucose than you’d get from glycolysis, but they also require oxygen. A cell with mitochondria will want to absorb glucose clouds and oxygen clouds. (Insert picture of a mitochondrion).
Chloroplasts allow glucose to be produced from exposure to sunlight (at the cost of carbon dioxide). Then, the cell can use this glucose to produce ATP (either through its cytoplasm or with mitochondria). (Insert picture of a chloroplast).
Vacuoles are used for storing compounds you have collected. Your cell is already able to store compounds in its cytoplasm, but vacuoles are far more efficient. (Insert picture of vacuole)
Toxin Vacuoles produce toxins (called OxyToxyNT). Toxins can be used by the cell to attack other cells.Toxins are produced from just oxygen. Once your cell has built up some toxins, press E to eject them (and try to direct it to the cell you want to kill). (Insert toxin organelle picture)
Your cell can also engulf smaller cells to consume them. Press G to enter engulfment mode, and move over a smaller cell to engulf it. Engulfment mode slows movement and consumes ATP at a steady rate.
Reproductase is what your cell uses to reproduce. You must have at least 5 to reproduce. Reproductase is made from oxygen, glucose, amino acids (made by your cell from ammonia), and ATP.
Editor
Every time you reproduce, you will enter the Microbe Editor, where you can make changes to your species (by adding, moving, or removing organelles) to increase your success in the environment.
Each generation, you have 100 mutation points (MP) to spend, and each change (or mutation) will cost a certain amount of that MP.
At the bottom of the screen it will say “Click to continue” or “Press spacebar to continue”.