A Meganob is what happens when a Nob gets enough Teef to get a skilled Mek to build them orky body armor, It is powerful enough to rival the likes of Terminator Armor, due to how it turns the wearer into a fucking tank, and its large Kombi-Shoota. Though other Orks mock the Meganobz for wearing so much armor, only the dullest would do so within earshot. Even a direct hit from a tank round is unlikely to do more than knock a Meganob over. For many, the only chance of surviving an encounter with an angry Meganob is to outrun him. To counteract this weakness, many Meganobz roar into battle aboard armored Battlewagons. This saves time that would be wasted slogging across the battlefield, and helps the Meganobz get stuck straight into combat. They are usually considered as a Warboss' right hand men and often the ones to be promoted to a Warboss if the original one died.
Ork kulture is a seething orgy of violence where the strong constantly assert their position over upstart, ambitious young Orks. In the extremely tough Kratocracy of the Orks, only the largest, toughest, and most aggressive Orks rise to leadership amongst the Greenskins. This makeshift "nobility" results in a class of Ork known as "Nobz" in their guttural language. Nobz are larger, richer and more aggressive than normal Orks, and never miss an opportunity to remind their fellows of it. These mighty Orks lead by example, fighting where the fighting is thickest and "encouraging" any recalcitrant Orks or Grots with cuffs and blows to get them into the battle. Orks instinctively obey those larger than themselves, provided they are a healthy shade of green. Most Orks would rather die than bow to a non-Greenskin's will (Unless if its Yarrick). A Warlord's or Warboss' decisions are enforced by this ruling caste.
In the case of Meganobz, they are even bigger and tougher then regular old Nobz being shy of the Warbosses and Warlords. While a Warboss may command his armies to go krump something, Meganobz are typically there to provide support and advice the rampaging Warboss on certain interests to be noted.
Meganobz being one alpha wolfs are able to gain some snazzy and shiny wargears such as a Twin-linked Shoota, the above mentioned Kombi-Shoota, Power Klaw, Mega Armor and Stikkbombs
On The Tabletop
"Dem Orks got a Mek for a Boss! Dat's jus' sad, dat is."
-Kaptin Bluddflagg, reassuring the truth
Ork Meganobz come in packs of three for 120 points, with a boss nob or a Big Mek for the ork with low standards, and a grot oiler.
Besides the weapons listed above they can replace the weapon set with 2 killsaws, giving them an extra die in armor penetration but you would lose out in shooting
MegaNobz are tough to move around the battlefield, it would be best to bring them on a battlewagon or trukk when in larger maps
The Big Meks get two additional weapons, the Teleport Blasta! and the Instant Death! for an extra 25 points