"'Til all are one" is a phrase knit throughout Transformers mythology and legend, often used as a rallying cry by the Autobots. It has been interpreted as meaning either until the end of the Great War, when the Transformers will shed their adversarial factional affiliations and all are one united group, or until all Transformers sparks are united in the Allspark of Primus. It is a hopeful slogan, a call for future unity.
As Megatron consumed the captured sparks of every Cybertronian, he urged "let us all become one!"
Dreamwave comics continuity
The Seal of Primus also had "'til all are one" written on it.
- "That thing stays in there till... till... "
- "All are one?"
- "Catchy. Yeah."
- - Prowl and Shockwave, the War Within
IDW comics continuity
The Megatron Origin miniseries shows a much darker use for the phrase. During a gladiatorial death match between Megatron and an unnamed opponent, the crowd begin to chant the phrase, apparently attempting to goad Megatron into finishing off his opponent. The phrase, as used here, would seem to suggest that the gladiators are expected to kill one another until only one remains (presumably the final victor).
This IDW series is based on the decline of the Roman empire. The audience are the ones to decide the fate of the defeated gladiator, so they can tell the victor to kill the loser.
The chant may signify the union of Alpha and Omega (beginning and end) of a Transformer's life.
Fun Publications continuity
Leave it to a Decepticon-allied Mini-Con to misunderstand what the Last Autobot meant by "till all are one." Broadside convinced himself and many followers that it meant all Mini-Con's would be remerged with the Last Autobot, ending their existence.
Robots in Disguise
The phrase is quoted by Leobreaker when he, Override, and Evac were sent to Cybertron to aid the Cybetron Defense Team in the episode United. Also, when communicating with the Autobots, Primus would intone the phrase in reference to their quest to restore his Allspark. Later, when he created the Ark out of the four Cybertronian starships signifying the unity of the Transformers, he said that all were finally one.
Revenge of the Fallen game
On the online multiplayer matches, one of Prime's phrases after killing an enemy is "'Til all are one".
War for Cybertron
The Autobot Council intones the phrase "Til all are one" to begin their meeting to decide who will be next to assume the mantle of Prime. It is also declared immediately after Optimus has announced the passing of Zeta Prime; the phrase may be used to ritually pronounce the death of the Autobot leader, while simultaneously expressing confidence in the new leader and faith in the continuance of the line, much like the intonation "The King is dead, long live the King."
Fall of Cybertron
Metroplex used the phrase during his last moments when he sacrificed himself to fuel The Ark.