Mekboyz can't resist improving something, even if it makes that something hideously dangerous in the process. Super stikkbombz are a case in point, each one is a bundle of krak bombz wired together to make one almighty bang.
Super stikkbombz work just like krak stikkbombz but have an armour penetration of 10+2D6. If a double is rolled on the 2D6 the attack is resolved as normal but the Mekboy using them is also caught in the explosion, he suffers a wound automatically but may attempt an armour save as normal.