The Rift Gate (also called the rift ring) is a Precursor artifact in Jak II. It is used to travel through time, and requires the Rift Rider to make it work, which requires two Precursor artifacts known as the Heart of Mar and the Time Map.
The Rift Gate is made of Precursor metal, as most Precursor artifacts are, and is made up of two rings and other smaller objects. The rings spin around while the various objects will travel around the gate. The ring reads "Brennan", "Rob", "Amy", and "Titus" in Precursor writing, which are names also translated throughout Jak II on various other objects.
Before Jak II
Towards the end of The Precursor Legacy, Jak and Daxter opened a large Precursor door using one hundred power cells, which revealed a massive, blinding light, ending the game. During that time through the beginning of Jak II, Jak and Daxter, along with Keira and Samos Hagai, discovered the Rift Gate, along with its vehicular component known as the Rift Rider. They moved it to the "lab", and began studying how it worked, thus starting Jak II.
In the beginning cutscene of Jak II, Jak, Daxter, Keira, and Samos Hagai are seen studying the Rift Rider, the vehicle that is used to travel through the Rift in the Rift Gate. Samos, knowing that Jak will somehow end up in Haven City due to his past experience around a decade from that time, noted that he "had experience with such things", and knew Jak could make it work. With that, Jak pushed the ruby button known as the Heart of Mar, which then activated the Time Map. Keira noted that it was reading out preset coordinates, that were apparently set to a date far into the future, and to a location not far from Samos' hut. A few seconds after the Time Map finished reading the coordinates, it slammed shut, and four nodes located on the large wheel behind the Rider began spinning, and shot lightning bolts at the ring, opening it, releasing a swarm of Metal Heads, along with their leader, Kor. Jak then pressed the Heart of Mar again, which projected the vehicle into the Rift, sending them far into the future.
Later in the future, another Rift Gate is found at the Metal Head nest. As the forces of the Rift slowly began pulling the ring apart, the Shadow (a younger version of Samos) and young Jak used it to travel to the past, prior to the events of The Precursor Legacy, whereafter it breaks and stops working, killing Kor along with it.
Other Rift Gates
Finally! The last Rift Gate has been opened!
When the Rift Gate is opened at the beginning of Jak II, Metal Kor says that the last Rift Gate has been opened, implying that there might be others. However, there have been no other references to other Rift Gates in the games so far.
- Two Rift Gates appear in PlayStation All-Stars Battle Royale as stage-related easter eggs.