As I am aware, there is only one Necron Cryptek model, but at 25pts for a potential Imperial Knight killer with a Voltaic Staff (Haywire Assault 4) coupled with a squad of Gauss Flayers (glance on a 6) I had to get a few more than one Crypteks.

The above Finecast model was terrible, but I did my best and straightened the staff and fill holes, but the kit does come with two upheld arms, so a fumble in the bits box (annihilation barge/chariot piece) and a Triarch Praetorian Abyssal Staff, Warriors legs and torso and head swap with a spare one-eyed Immortal/Deathmark head and voila, two for the price of one.
After an article by Zen40K on converting Crypteks using WFB Banshee parts, I came up with the above and from the many posted already in various forums, the following from a WFB Wraith too.
I'll post when done. Thanks for stopping by.