Here are a coupe of rogue guns for use in defending town walls. Rogues performance is equivalent to that of the 68-pounder, albeit with a slower rate of fire. This can be explained by the 68's use of the percussion cap for firing, while the rogue still uses the "prick and prime" method.
Rogues are not much seen in the field, being very heavy and difficult to maneuvre, but they are useful in knocking down the walls of smaller Martian states. Any siege train on Mars expecting to carry the day will feature a battery of rogues, and any municipality hoping to resist will mount a few on the walls, as a deterrent.
These are part of a three-gun set from Scotia Grendel - you will find them under the Medium Dwarven Artillery. As resin-cast, there is a bit of "greeblische" around the base, simulating churned-up dirt from the field. This might bother the extra-fastidious when deploying them on a stone parapet.
I wasn't entirely certain these would scale well with my RAFM Martian gunners, but they do.
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