Coat of Arms for Megatron

I did one for Optimus, so I thought it's only fair to create some attributes arms for his nemesis, Megatron.

Blazoned: Tierced per fess Argent, Purpure and Sable a cannon Or. Atop the sheild, a helm mantled Sable and doubled Purpure and from a wreath Sable Purpure a Decepticon insignia Purpure is set for a crest. To be carried in an escroll below the shield the motto: "pax per tyrannidem" (peace through tyranny).