Infectonator!

Infectonator! is a series of turn-based strategy web games (with one spin-off with slightly different premises), all based upon making chain reactions and getting upgrades. Originally a video game series on Flash that debuted on December 4, 2009, it later became available to play for mobile devices on iOS and Android.

Games

 * 1) The first entry, 60 Second Edition, released on December 4, 2009, had the player to try to infect and zombify as many people as possible in a single minute. Breaks were allowed for making upgrades, but once the player ran out of time, that was it.
 * 2) The second entry, Christmas Edition, was the same, but instead of 60 seconds, the player had 25 days until Christmas, and each turn took a day. Also, the player got to kill Santa.
 * 3) The third game released was Necronator, while a large part of the interface and controls in World Dominator remain, the setting and gameplay are completely changed to Medieval times, with the player commanding a Necromancer who tries to take over the world with his undead. Unlike the other games, units are built over time from a preset building with income slowly provided, instead of being created from an infectious chain reaction. However, zombies and the original "infection" chain reaction ability from the first three games remain.
 * 4) Necronator 2 was the fourth game in the series. It abandoned the gameplay of World Dominator for a complete strategy feel while modifying the aesthetics and gameplay of its predecessor. The zombies and infection abilities are still present in a greatly nerfed form. However, the main draw is the multiple campaigns and huge variety of playable units and races.
 * 5) Infectonator 2 is the latest game in the series and returns to the formula of the original game. It retains most of the game-play of the original World Dominator while improving the visuals and tightening the core elements that made the original successful.