|“||..for they will be portals, gateways to a civilization far beyond our own.
The Scrin Thresholds (also known as Gateways) were the enormous superstructures constructed by the Scrin at nineteen Tiberium-rich locations across the Earth. All but one of these towers were destroyed by GDI at the end of the Third Tiberium War.
|“||Holy crap, that tower's enormous!
- GDI soldier witnessing how large the tower is
The Thresholds are apparently gateways, primarily used to extract large quantities of Ichor (Tiberium) in the immediate area and process them to the Hub, as said in the Scrin intelligence database, although it is presumably also used as a gateway for Scrin units to transport through via the link to the Hub (this apparently worked both ways; Foreman 371 used a tower to escape Earth on his Mothership, warping to the Hub).
The Scrin created the Thresholds while GDI forces were distracted by Scrin attacks on civilian targets. The Thresholds were well protected, each having three Phase Generators warping them out of sync with the physical plane of reality; rendering them completely indestructible.
Nod followed a plan to use the Threshold technology. Its forces captured a Nerve Center in Italy, gaining the codes necessary to use the Scrin Thresholds.
The GDI Commander successfully destroyed a Threshold near Rome, first by destroying its Phase Generators, rendering them vulnerable to physical attack. GDI then went on to destroy eighteen out of the nineteen towers. Nod's Commander was sent to what used to be Mediterranean Coast. He successfully managed to stop GDI's attempts to destroy the last tower in southern Italy, while the Scrin hastily completed it.
The final tower was protected with extreme ferocity by one of Nod's highest-ranking commanders, believed to be Kane's second in command. This Commander destroyed all GDI presence in the region. As such, the tower phased out of sync with the physical world when it was completed, and now stands impervious to human attack and natural upheavals and is under close Nod supervision, believed to be acting under Kane's personal orders.
With the Relay Node destroyed, it seems unlikely that the Scrin will use the remaining tower, located in Italy, for anything at all, at least in the near future. Nod is apparently keeping a low profile, despite their tower being invulnerable, and GDI scientists believe that the tower is completely inert.
Location of Scrin Thresholds (Third Tiberium War)
1. Midwest United States
2. Texas, United States
3. Near Bogotá, Colombia
4. Near Iquitos, Perú
5. Acre region, Brazil
6. Southern Italy (still intact. Also, "Kane's Tower")
7. Balkan Mountains, Europe
8. Southern Turkey
10. Northern Iraq
11. Afar region, Ethiopia
12. Ugandan-Congolese border
13. Angolan-Zambian border
14. Assam, India
15. Guangdong, China
16. Shores of the Caspian Sea, Turkmenistan
17. West Papua, Indonesia
18. Near Port Augusta, Australia
19. Near Rome, Italy