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The Ion Cannon was a space based particle beam cannon designed to engage any target upon the face of the earth with ease. It was GDI's ultimate ace-in-the-hole, and a way to counterbalance Nod's use of nuclear weaponry during the First Tiberium War without resorting to similar weapons and producing massive levels of fallout.

The project lead for the Ion Weapons development was Doctor Wong Hu Chan, an accomplished scientist. Kane even acknowledged Doctor Chan's brilliance, immediately prior to sending his best commander to assassinate him to stall the research. A Nod sniper managed to get within range and kill Chan. This was a setback for GDI, however, they still managed to finish researching the weapon in time for the Sarajevo offensive.

The Ion Cannon weapon systems have been upgraded continuously ever since their introduction in late 20th century. In the first two Tiberium wars, the Ion Cannons consisted of only a single concentrated ionized beam. In the Third Tiberium War, GDI has switched to a more sophisticated system. 8 tributary beams ionize the gas in the target zone, then the Ion Cannon fires another beam from its main cannon to ignite the volatile ionized gas, generating a colossal explosion, shattering practically everything in the target zone. Use in Tiberium fields has seen the whole field wiped clean of any Tiberium - very handy in Red Zones.

As of 2047, there were four versions of the Ion Cannon: Mark I, the first Ion Cannon, emmitted a single beam onto the Earth's surface, using its heat and force to destroy targets; Mark II, the second Ion Cannon produced, emmitted multiple beams that did the same as the singular beam of the Mark I; the Mark III, the Ion Cannon used in the Second Tiberium War, used heat and force so powerful, it created a wake around the target, damaging nearby buildings and vehicles; and the Mark IV, the Ion Cannon used in the Third Tiberium War, it could either fire eight tributary beams to ionize the gases in the air, before using main beam to ignite the volatile gases to create a wide destruction radius, or it could direct all of its power into main beam discharge directed towards a single reinforced land-based or space-based target (latter was used to destroy Temple Prime in Sarjevo (and resulted in liguid tiberium blast) and for attempted destroying of Scrin starships in orbit)

[edit] First Tiberium War

The Ion cannon was first deployed during the closing stages of the First Tiberium War, instantly becoming a powerful asset of the organization. While its power output was still relatively weak, it was widely used by Global Defense Initiative commanders worldwide. As such, the command introduced queueing systems for the Ion Cannon network, resulting in waiting times for commanders requesting the cannon's assistance.

The Ion Cannon of this era required an Advanced Communications Center to be constructed to properly uplink with the orbiting weapon.

The cannon could be targeted accurately either using the GPS system or a specially designed ion cannon beacon.

[edit] Second Tiberium War

In the years between the first and second Tiberium wars, the Ion Cannon's basic design changed little in essence. GDI engineers were able to increase its power several times as well as improve tracking systems. Also, the queuing process was simplified and the Cannon's positioning engines improved.

To access the Cannon, commanders only needed to construct a single Upgrade Center and an Ion Cannon Uplink tower there.

[edit] Third Tiberium War

In the years after the crisis, GDI expanded its power base in space, overhauling the Ion Cannon's design and power. The new Ion Cannon's power was amplified to the point of being able to obliterate entire bases in a single blast or destroy Scrin capital ships.. Unfortunately, the new cannon still suffered from the lack of speed positioning and the queuing system was still in place. However, the final result was still considered worth the drawbacks.

The building required for creating an uplink to the cannon is the Ion Cannon Control Center installation.

Other than serving as a super weapon that obliterates enemies that are on the ground, the Ion Cannons can also serve as defensive weapons against threats in space.

The ion cannon network was disabled at the beginning of the Third Tiberium war by Nod to allow them to use a nuclear missile on the Philedelphia, however it was brought back online by the time Nod forces were pushed back to Sarajevo. This was all a part of Kane's plan, as the ion cannon network detonated the Liquid Tiberium bomb, causing an explosion that killed millions throughout all of Eastern Europe. The blast attracted the Scrin to Earth, although they were caught off-guard as GDI's ion cannon system began attacking their landing ships. The Ion Cannons were also instrumental in the GDI attaks on Scrin Threshold towers, being able to completely destroy the massive facilities once the phase generators protecting them were destroyed.