Cross Virus is the 19th web game by Dan-Ball released on 18 July, 2014.
There are currently 25 stages available. In each stage, there is a 11×11 grid filled with a certain number of viruses, the number of which depending on the current stage. Several stages also have blocks preset. Players try to stop the viruses from reproducing by using blocks to trap the viruses. As the viruses will reproduce during the block placing process, players have to place blocks intelligently to keep the viruses under control.
The player is given three blocks each turn that can be placed by left clicking one of the grid squares. These blocks are marked red and can be taken away by left click before the third block is placed, ending the turn.
After the third block is placed, the three blocks are fixed, and the virus will replicate by occupying the grid square directly next to it (but not diagonally) as long as the grid squares are not occupied. The player then receives a new set of three blocks and the game continues.
Taking the situation depicted at the right as an example, by placing the thrid block at the position marked with a blue star, the three blocks are locked in. The virus then spreads, creating 2 viruses below and to the right of the virus, which were empty spaces before. It cannot spread upwards and to the left as these spaces are blocked.
The stage is complete when there are no possibilities for the virus to spread, at which the virus count will be used for a star rating. As long as there are less than 80 viruses, a star is given. Up to 3 stars are awarded if the player completes a stage with a low virus count.
Virus number for 2 and 3 Stars
|2 Stars||≤ 3||≤10||≤17||≤32||≤18||≤24||≤40||≤24||≤22||≤19|
|3 Stars||≤ 2||≤ 8||≤15||≤28||≤15||≤21||≤38||≤23||≤21||≤16|
|3 Stars||≤38||≤ 9||≤22||≤18||≤29||≤18||≤32||≤22||≤24||≤29|
|Version||Date||Thumbnail||New features and changes||Blog|
|1.4||10/08/2018||Bug fix (Scrolling while playing the game on smartphones).||jp/en|
|1.2||29/08/2014||Stage addition (21-25).||jp/en|
|1.1||08/08/2014||Stage addition (11-20).||jp/en|
- ↑ The original blog is written in Japanese. A link to an automatic translation into English by Google is also available.