Editing Chapterhouse Studios

Ahh GW making rules for models that don't exsist. This can be really fucking irritating to quite a few people as, GW set up some awesome rules for a model *AHEM* GIANT SCARAB THAT ATE SHIT *AHEM* and then leave the community to wallow in their own anguish as said models are NEVER MADE, a few examples include:
Necrofex colossus (8th edition, warhammer fantasy vampire counts, book of origin: Monstrous Arcanum)
Parasite of motrex
Doom of malantai
Dwarven airship
Chaos siege tower
Old zogwort
Wazdakka gutsmek (te forge world ork biker boss was a nice substitute though!)
So on and so forth.....

This is normally due to the fact that GW has "other things on their mind" this includes Matt ward spending the lone hours of the morning masturbating while making the rules for GK and 'Crons even more OP.

So what can you do?  Well you could sit there and end up dying in hopes of seeing your model come to life, or you could do a conversion. A conversion is the easiest and only solution you have as it's the only way you'll be able to field said model, or if you didn't have the time or the moolah, then you could just declare a model to be that follows the rules of the minature that wasn't released (e.g use a weird boy as Old Zogwort, problem solved) however this can be quite a turn off for the player as there is not the same feeling of tabletopness you get as fielding a model as what it is, not declaring it to be something else.                  

*sounds of gender inequality can be heard in the distance*

Anyway to summarise, unless GW has released the model, either get converting, start waiting, or suck it up and just use the damn rules.

P.s the scarab I was referring to is the Khemric Titan