"Dose Orks got a Mek for a Boss! Dat's jus' sad, dat is."
- – Kaptin Bluddflagg, on the subject of Big Meks
Unlike their Painboy cousins, Mekboyz do demonstrate a more typically orky sense of ambition. And so it is that a Mekboy can grow bigger and stronger and even more inventive, until he has become a figure of respect and awe in the eyes of the common Ork Boyz. This is a Big Mek, essentially a more tekky version of the Warboss. Though they are often content to leave the hassles of leadership to a Warboss and simply run their own things as a sort of second-in-command, Big Meks have been known to lead their own WAAAGHs as well.
When a Big Mek is in charge, naturally, there's a lot more emphasis on tek over boyz. Aside from leading Speed Freek kultz, Big Mek Waaaghs usually abound with all the various walkers and tanks they can set up, heavy artillery, Flash Gitz, Lootas, and Trukks.
They are usually the ones in charge of building a Stompa or a really big Gargant; if you see a Stompa or Gargant waddling across the battlefield, you can bet your ass that a Big Mek is somewhere nearby. Big Meks usually can be identified by their use of heavy armed and advanced (by Ork standards) armour. Some are so decked-out in technological bling that they appear more like Deff Dreds and mini-Gorkanauts than an actual Ork.
Gorkamorka is a prime example of the sort of "ork kulture" likely to breed a Big Mek Waaagh!
A Big Mek will quite naturally have some of the fanciest equipment around. These options can get pricey in points, but are so good you rarely see an ork army without at least one of them, and since they're exclusive to the Big Mek, they're a big part of why people bother to take them over a Warboss.
A warp field projection weapon that uses the warp to teleport its ammunition inside the armor of a target. Potentially deadly to even the strongest tanks, but with no small amount of risk. Tearing the warp a new one is an iffy proposition at best, and this is being done by Ork tech. It's possible that, rather than sending a screaming, enraged grot into your target's lungs, you simply open a void portal, consuming your target entirely. It's also possible for that same void to open up on the weapon, sucking down the Big Mek that fired it.
- Kustom Force Field
An extremely popular support choice. The KFF creates a sphere around the Big Mek, protecting any allied units within from shooting. This works wonders for a large number of orks trying to get into choppa range while running right at an Imperial Guard trench.
An extremely powerful blast weapon in an army that rather lacks a good anti-armor punch, this weapon would be a 'must have' if not for two flaws. First, it must be mounted on mega armor, limiting the Mek's maneuverability. Second, it's subject to scatter, and only has the range of a pistol. But then, it wouldn't be orky if it wasn't capable of frying your own troops.