- "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[src]
Jupiter, previously known as Tinia, was a member of the First Civilization. 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. Later, a holographic projection recorded before his eventual death started to act in his stead.
In 2012, his projection spoke with at least one First Civilization descendant: Desmond Miles.
- "Both before the end and after, we sought to save the world."
Upon the outbreak of the Human-First Civilization War, Jupiter was one who chose to find a means of preventing the coming disaster.
On the construction of Temples to research methods of doing so, Jupiter, Minerva and Juno were given the responsibility of sorting and sampling the information. The three convened in the Grand Temple, where all the findings from the 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]
In the year 2012, Jupiter spoke with Desmond himself – who he referred to as "the Cipher" – in the nexus of time. There, he told him of his work with the Temples and of the First Disaster.
In order to prevent a repeat of the catastrophe, Jupiter urged Desmond to seek out the Grand Temple and told him the means of opening the way.
- 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 could be 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 (the best and the 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 mythology, Minerva is his daughter; Juno however is his sister, who he married.
- Jupiter was briefly seen in the holographic projections inside the Grand Temple, which were shown to Desmond by Juno, who described the six solutions that the First Civilization had worked on.
- Tinia was one part of the trinity of gods who ruled over the Etruscan gods. The trinity consisted of Tinia (Jupiter), Uni (Juno) and Merva/Mera (Minerva).