Virus

Viruses are green balls with spiked edges scattered around the map.

+132 Mass
When a cell of 133 mass or greater consumes a virus that has not been fed, they will split into many pieces, making them easy targets for other cells, but gain 100 mass.

The player will be able to merge back all of their cells at once after 30 seconds or so, as it depends on the mass of your cell.

-133 Mass
Players' cells not large enough to consume a virus will pass through it harmlessly, making it a safe haven for small cells. The virus will also hide a small cell inside of it, so small cells can use viruses to hide from large cells or plot a sneak attack, though, when a player's cell is larger than another player's cell and very near to 133 mass, he will not hide behind it, but rather be seen in front of it.

Gain of Mass
Once a player has 16 independent cells, running into a virus with a cell of over 132 mass will result in the virus being consumed without additional splitting, only gaining 100 mass.

Creating a Virus
A new virus can be created by a cell by ejecting 7 pieces of mass at a maximum by using the key.

When the virus is given the seventh piece of mass, it will eject another virus in the direction the player is moving.

This mechanic is often used to attack larger cells who would otherwise be impossible to consume for the player.

Keep in mind that when you are in range to give mass to a virus, you are also in range for the ejected virus. Ejecting viruses at other cells has considerable risk of counterattack. Viruses that are closer to ejection appear swollen and have more spikes.

Limit of Viruses
While the exact number is unknown, there is an upper and lower limit to the number of viruses that can exist on the map.

When the lower limit is reached, a virus will randomly spawn on the map (not on top of a cell).

When the upper limit is reached, all mass ejected towards viruses will pass through them so that cells cannot create more viruses.

Removed Dark Viruses
In Experimental Mode 5% of the viruses were a little larger and a bit darker on 2015-06-11, they were removed the next day.