This is a really awesome monochrome masterpiece, and rather apt for 2020.
A downloadable game
16K ZX81 - 2014
"That is not dead which can eternal lie... in a petri dish" (with apologies to HP Lovecraft)
The sequel 2010's VIRUS.
When Virus was released in 2010, I was proud of the game I had written - I still am - as a shoot'em-up that required a certain strategy to playing it, as you had a limited amount of bullets to tackle the outbreak with. Pandemic is a sequel to Virus, but with unlimited ammunition you can now go in with all guns blazing without fear of running out of ammo at that pivotal moment (just the fear of being suffocated by the virus)
The game isn't just Virus with some tweaks and new levels though, the engine has been redeveloped to cater for more enemies, diagonal movement and firing, virus generators, and key walls to name but a few improvements. The game is also three times larger than its predecessor, boasting 24 levels of biological warfare.
Just don't shoot the food!