Morkanaut
The Morkanaut is a massive, blocky, primitive battlesuit created by the Mekboyz and piloted by particularly skilled, or deranged, mekz. Morkanauts make use of the most fantastical weapons and gizmos that their creators can devise; a pair of twin-linked big shootas, twin rokkit launchers, a skorcha and a suped-up power klaw make up the vanilla stuff, for when the kustom mega-blasta and kustom mega-kannon aren't feeling like playing, and they can sport kustom force fields to make them extra hard to battle.
For Maximum Lulz give the Morkanaut Extra Armour and Grot Riggers. Then buy a Big Mek and pay for both Da Fixer Uppers and a Kustom Force Field (if you picked the Morkanaut, you can pay for its Forcefield instead). 360pts minimum, but the 'Naut will absolutely refuse to die thanks to a 5+ Invulnerable against shooting, It Will Not Die, ignoring Crew Stunned & Shaken results and the ability to fix either Weapon Destroyed, Immobilized, or Hull Points on the roll of a 3+. Or you can do a discount version of the above by using Burna boys with maximum meks, or even the slotless meks each HQ choice unlocks.
Although in many ways a super-sized Deff Dred, its size 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. The Morkanaut's brother is, of course, the Gorkanaut.