No, that name didn't come from my own imagination. Kozilek is one of the first Eldrazi creatures spoiled by Wizards of the coast
First of all, what jumps to the eye, is the semi-transparent frame, similar to Ghostfire. This is because Kozilek, as all of the eldrazi as far as is known, is colorless. Not an artifact (most of them are colorless), but simply colorless.
Next comes the mana cost. 10. Simply 10. This seems a bit hard to hard cast, but summoning trap and dramatic entrance jump to my mind.
Next, the power/thoughness. 12/12 is something to be respected. Damaging this "little" guy is a really hard task.
Starting from the middle, Annihilator. This new ability seems to be something like:
Annihilator X (Whenever this creature attacks, defending player sacrifices X permanents)
This seems like a great ability. Attacking with this can rid your opponent of needed lands, blocking creatures, pesky enchantments, whatever. I think the "butcher" part comes from this ability.
The Truth part seems to come from his first ability. When this comes into play you draw 4 cards. Besides getting a big beast in the table, this also freshens your hand up with new solutions.
Also, when this baby dies, it goes right up to your library, taking with him all your used up spells. A blast against mill.
I realy REALY want to draft this one and i really want to see more eldrazis.
For reference, here's the official spoiler link
So sit back, relax, and let me flay your mind.