The Autobot Matrix of Leadership (also known as the Creation Matrix or rarely, the Autobot Matrix of Power or the Matrix of Light) is an artifact of great power, traditionally carried by the leader of the Autobots. Although its appearance differs slightly from universal stream to universal stream, it generally appears as a glowing crystal sphere encased within a hollow metal shell, with a handle on either side.
By most accounts, the Matrix is a conduit for the power of Primus, the creator-god of the Transformers, serving as a means of access to the Allspark, the “afterlife” of the Transformer race, through which it can either bestow new Transformer life, or provide its wielder with a means of communicating with the deceased leaders who have come before them. These divine powers put it at the centre of much Autobot religion, spirituality and prophecy; while many Decepticons are less inclined to believe in its divinity, they certainly covet the increased physical power it is known to convey upon its holders, and several have made obtaining the Matrix one of their primary goals. As one of the embodiments of the power of Primus, the Matrix is antithesis to Unicron, and one of the very few things the chaos-bringer fears.
A dying Optimus Prime, The Transformers: The Movie