- "I see you still have many questions. Who were we? What became of us? What do we desire of you? You will have your answers. Only listen, and I will tell you how."
- ―Jupiter to Desmond Miles, in the Synch Nexus, 2011.[src]
Jupiter was an Isu scientist, and a member of the Capitoline Triad. Alongside Minerva and Juno, he took charge of the gathering and testing of information within the Grand Temple, in order to circumvent the First Disaster.
Jupiter was known by many names both throughout and after his lifetime due to his long life and legacy as a god to humanity. His earliest known name was Tinia, but with the evolution of human religion, a number of distinct and sometimes contemporaneous appellations arose. He was known as Zeus  to the ancient Greeks and Egyptians and Jupiter to the ancient Romans and the modern day Assassins.
- "Both before the end and after, we sought to save the world."
On the construction of Temples to research methods of doing so, Jupiter, Minerva and Juno were given the responsibility of sorting and sampling the possible solutions that would prevent the disaster. The three convened in the Grand Temple, where all the findings from the lesser Temples were gathered, in order to select and test them.
However, though they found each succeeding method to be more promising, the First Disaster fell upon them, burning the Earth and wiping out nearly all members of the First Civilization.
- "Take my words. Pass them from your head into your hands. That is how you will open the way."
- ―Jupiter to Desmond.[src]
The Second Disaster
Jupiter did not appear when Desmond entered the Grand Temple as the Second Disaster approached, as the Cipher conversed mostly with Juno. Jupiter's image was used by Juno when showing Desmond holographic projections of the Triad's proposed solutions to the First Disaster. Later, Minerva appeared and revealed that she and Jupiter imprisoned Juno and allowed the First Disaster to occur rather than allow her to enslave the Earth. Minerva also revealed that she and Jupiter (or Tinia, as she called him) spent many centuries following the First Disaster walking among humans trying to rekindle the spark of civilization.
As the Greek god Zeus, Jupiter is regarded as the chief of the Twelve Gods of Mount Olympus. Zeus is infamous for his various relationships with multiple individuals, divine and mortal alike. Via these unions, Zeus is considered to have fathered multiple heroes of Greek mythology, including Herakles, Perseus and Polydeukes as well as Greek deities, including Persephone, Dionysos, Charites, Ares, Eris, Hebe, Hephaistos, Pan, Apollo and Artemis.
- Jupiter was referred to as Tinia in the artbook of Assassin's Creed: Revelations and the Revelations novel, as well as throughout Assassin's Creed III.
- Jupiter was represented by one of the statuettes that could be collected in Monteriggioni, and was paired with a statue of Minerva. The pair's description read "Here sits the king of all Olympus and beside him stands wisdom, to guide his rule."
- Jupiter, also called Jupiter Optimus Maximus ("best and greatest"), was the Roman King of the Gods, and was the equivalent of the Greek god Zeus in both characteristics and personality.
- Jupiter's helmet resembled an eagle, his representative animal in Greco-Roman tradition and a common symbol of the Assassins.
- In the Assassins Creed: Revelations novel, Jupiter referred to Minerva and Juno as his sisters. However, in Greek and Roman mythologies, Minerva/Athena is his daughter, while Juno/Hera is indeed his sister, whom he married.
- Jupiter was briefly seen in the holographic projections inside the Grand Temple, which were shown to Desmond by Juno upon describing the six solutions that the Isu had worked on.
- Tinia was one part of the Capitoline Triad that ruled over the Roman gods. The triad consisted of Tinia (Jupiter), Uni (Juno) and Merva/Mera (Minerva).
- Assassin's Creed II (mentioned only)
- Assassin's Creed: Revelations (first appearance)
- Assassin's Creed: Revelations novel
- Assassin's Creed III