Forgefiend
You want a Daemon Engine with huge firepower and capable of chewing up the odd Imperial guardsman whilst it does it? Then you sir need the Forgefiend. Guaranteed by the Traitor Legions and the Dark Mechanicum, the Forgefiend was designed in mind with the idea of causing widespread death and mayhem from afar. On four study legs, the forgefiend carries two hefty Hades autocannons, capable of blasting through even the most courageous (or dull-witted) Ork. Yes, when you have the power of the warp burning into your chest, a burning gift from the forges that created this fine machine, then you need look no further.
For those desiring a bit more of the arcane, then it is no problem to remodel your forgefiend into a ceberite. No, not one of those kinky leather lovers from Hellraiser, a monstrous machine with huge plasma cannons and a dripping mouth just waiting to cause pain and misery. Yes, the forgefiend truly can see to all your slaughtering needs. The forces of Chaos vouch for it!