Morkanaut
The Morkanaut is a large, heavily armed walker created by the Mekboyz and piloted by a particularly skilled, or deranged, Mek. The Morkanaut's brother is, of course, the Gorkanaut.
Morkanauts make use of the most fantastical weapons and gizmos that their creators can devise. The Morkanaut's weapon loadout consists of a Kustom Mega-Blasta, a Kustom Mega-Zappa, two Twin Big Shootas, two Rokkit Launchas, and a Klaw of Mork (or possibly Gork). Optionally, it may also take a Kustom Force Field. Since the KFF grants a 5++ invulnerable save against ranged attacks to friendly Ork units within 9" (including itself), you will take it.
In contrast to the anti-GEQ buzzsaw that is the Gorkanaut, the Morkanaut's high strength, high AP main weapons are best used for eliminating vehicles and elite infantry. It also loses 2 melee attacks compared to the Gorkanaut, but gains the aforementioned force field option. Either way, the Morkanaut is more than capable of reducing an undamaged battle tank into scrap in one turn.
Being much larger than a Deff Dred, the Morkanaut is essentially a small Stompa. Its size therefore allows it to carry up to half a dozen passengers in its armored belly, heaving them out to begin the slaughter on their own before getting back to fragging shit.