Atomic Powered Interplanetary Burrowing & Siege Weapons For Your Old School Space Opera

Giant Shocker Machines ( Atomic Powered Interplanetary Burrowing & Siege Weapons) 

Crew 4  HD+80 AC:0(19)Atk: Fusion Heat Ray 10d6 in a 20 yard radius, (save vs breath weapon to avoid), Move 24 Save As Pilot CL/XP +8 levels 

     These are heavily converted asteroid mining machines that have been used extensively throughout the Outer Colonies. Now being these terrible weapons are being deployed by terrorists, pirates, &all types of scum. The weapons are being sold through several black market weapon dealers & fetch millions of credits. They use reverse engineered alien technology found aboard several ancient space freighters around the Delta Gates. These monstrous machines are used to break through the defenses of  interstellar city states & planetary defenses.
Recently these terrible beasts of war have been seen being deployed in the deserts of Mars. Who knows what or where they'll strike. Often times these machines will be equipped with a  secondary anti personal weapon such as pop up blaster cannons or the like. These often do 1d4 per shot & have a range of 30 yards.
These vehicles are powered by alien atomic reactors with a half life of 100  years & seldom run out of power. The problem with these weapons is their propensity for maintenance & up keep which costs about a 1000 credits per month. With fleets of  ten or more of  these weapons this can become very costly over the life of the weapon's plat form.