Just hope the 'cult' data slate actually comes out :p
About the codex:
As someone stated above, I wouldn't put it past GW to adopt this type of sales approach for future books. I.e. release just the basics for the parent book, then make players pay more for their favorite/powerfull/fluffy units in the form of digital releases.
Noodling the book I found a funny rules interaction:
Deep striking mawloc arrives under an enemy unit, resolves both template attacks, and fails to kill enough models to allow it to be placed. It then mishaps, rolls 'misplaced', and is placed by the enemy player.
'Your opponent may deploythe unit anywhere on the table (not in impassable/lethal terrain) in a valid deep strike formation, but without rolling scatter.'
Per terror from the deep (mawlocs special deep strike attack) it can hit friend and foe. So if he fails to come in and gets misplaced your opponent gets one (Mabey two) no scatter S6 ap2 large blast template attacks to throw back at you... Lol.
My next thought involved a mawloc bouncing in this fashion back and forth, decimating both armies. :p
Walk without rhythm.