As for the image you provided, what are we to make of the clear depiction of a scythe, a farmers tool, on the side of the 'rocket'?
It is the armory car/wagon + soul hauler of Mr. Death.
If you notice carefully, there are interchangeable scythe blades neatly packed in front of the scythe.
The scythe is indicated as an advanced model with additional support hands. Death has indeed advanced technologically.
And the Comet looks like a Coffin.
The depiction is a visiting card from Mr. Death.