The Tremor was a cataclysm that happened at 2013. The disaster caused permanent changes to Earth's environment as well as unleashing monsters that caused most countries (including the United States, China, and Russia) to go bankrupt. This event and its subsequent transformation of Earth into PT Earth are depicted on Tremor.
The Tremor happened on July 16th 2013, when an asteroid collided with Earth, causing earthquakes and tsunamis around the world. The collision with the asteroid also caused other unwanted disasters. The size polar ice caps somehow increases over time, causing the northern parts of many nations covered with ice and a strange substance only known as Zenzium began spreading across the globe. The United Nations dissolved a few days after the Tremor and many countries ceased to exist a few weeks afterwards.
As countries began disappearing, the citizens of the countries went wild afterwards. They rob, raid, and pillage everything they can see all in the name of survival. Some like the Initiative went underground, waiting for the day they can retake Earth while others travels across the dangerous landscapes of the Earth, with the various strange lifeforms from giant living blobs to towering monsters that came straight from a TV show. The Earth after the Tremor was subsequently called PT Earth, standing for: Post Tremor Earth.
The Tremor brought several devastating changes, most notably the environment. To ease the safety of their members, the Intiative created the concept of 'Zones' to differentiate the areas that are safe and dangerous.
- Blue Zones: Blue Zones are places where the surface suffers minor to no damage at all. These zones are the perfect place start settlements and to gather resources safely. Some Blue Zones includes Central Africa, Cuba, and the Falkland Islands.
- Yellow Zones: Yellow Zones are places where the surface has been moderately affected by the Tremor. Normal humans can live in yellow zones but may need protection as strange creatures lurks around these Zones as well as minor Zenzium poisoning. Some Yellow Zones includes Brazil, Guatemala, Ireland, and Nepal.
- Red Zones: Red Zones are places where the surface has been greatly affected by the Tremor. It is uninhabitable as giant monsters roams the lands and Zenzium radiations reach incredibly high levels. The Red Zones includes Germany, Hungary, Italy, and the United States East Coast.
- The entire concept of the Tremor is based on the Tiberium from Command and Conquer.