The Hellhammer was built to provide short-ranged fire support in difficult conditions (like city fights). It certainly excels at this role, as its main weapon, the Hellhammer cannon, can exterminate defenders no matter where they are hiding or what armour they are wearing (although the devastation is contained within a small area). However, its formidable armament doesn't end there - it is also armed with co-axial Autocannons, Demolisher cannons, Twin-linked Heavy Bolters and Lascannons and Twin-linked Heavy Flamers in each of the side sponsons.
The Hellhammer's primary powerplant is a Phaeton pattern 110 square kilo-cubits Adaptable Thermic Combuster, supported by a Gravis pattern Thaumic Resonance Crystal Generation Unit. Besides the standard Smoke Launchers and Searchlight it can be adapted to mount a Hunter-Killer Missile and/or a pintle-mounted Heavy Stubber/Storm Bolter. Some Hellhammers will replace the side sponsons with extra armour or even add two additional side sponsons, each armed with a Lascannon and twin-linked Heavy Flamers.