1) Each unit on the main game interface corresponds to a level.
2) Subsequent levels will unlock sequentially after meeting the conditions of previous levels.
3) The largest unit (with a "?" icon) randomly selects one level, excluding the tutorial levels, to enter.
4) The first 4 levels are tutorial levels, with a demonstration video showing the gameplay before the level starts.

Press Alt + Enter during the game to switch between fullscreen and windowed modes. After switching to windowed mode, you can resize the window by dragging it. The game uses a default 16:9 layout, so when adjusting the window size, try to maintain the aspect ratio to avoid incomplete interface display.

In the top-left corner of the level, as shown in the image above, the current level's completion conditions are listed. There are at least 1 and at most 4 conditions, all of which must be met to complete the level. These four conditions are as follows:

Left 1: The required number of virus units and the population limit for this level. When the virus count reaches 80% or more of the population limit, this victory condition is considered fulfilled.

Left 2: The number of cells that need to be destroyed in this level. Cells are objects marked with a DNA symbol that can replicate viruses. The number on the right side of the "/" indicates the required number of surviving cells to complete the level. Generally, all cells within the level must be destroyed to fulfill this victory condition.

Left 3: The required number of white blood cells for this level. The level's victory condition is only fulfilled when the number of white blood cells in the level exceeds the number on the right side of the "/".

Left 4: The number of bleeding points that need to be created in this level. The victory condition is fulfilled only when the number of bleeding points (shield-shaped objects that have been destroyed) in the level reaches the number on the right side of the "/".

The electrocardiogram on the right side of the level interface represents the current health status of the virus host. When the ECG becomes redder and the heartbeat intervals grow longer, it indicates that you are getting closer to fulfilling the level's victory conditions.



White blood cells are units automatically produced by the host's immune system. Typically, they are generated in the scene only after the host's immune system detects a viral attack, with a certain delay. The number of white blood cells is influenced by the types of surface antigens present on the viruses. Theoretically, the more types of surface antigens carried by the viruses in a level, the greater the production of white blood cells. Since surface antigen mutations reassign colors to the viruses, we can understand this as: the more colors the viruses have, the more white blood cells will be produced.

Each white blood cell carries one or more sets of antigen codes. A white blood cell can only phagocytose viruses that correspond to the antigen codes it carries.



When selecting a virus unit, the number displayed inside the virus represents its generation. When a first-generation virus replicates, the newly produced virus is a second-generation virus. Replicating a second-generation virus produces a third-generation virus, and so on.

The higher the generation of a virus, the greater the probability of mutations in its surface antigens during replication. Additionally, the likelihood of "?" gene fragments transforming into other functional gene fragments also increases.

This is a crucial concept. Virus generations should be kept within a reasonable range to ensure that "?" gene fragments have a sufficient conversion rate, while also preventing excessive new surface antigen mutations that could trigger the host's immune system to overproduce white blood cells.