In it's present form, there are a couple of ways to play it out. Drainpipe +
Thoughtseize provides discard to keep their threats low. Pack Rats provides a way to play against mid-range style decks, or aggro if you want to play defensively. With the
Drainpipe Vermin +
Mutavault you have a lot of ways to make your
Pack Rat larger.
The
Read the Bones +
Scrivener make it so that your game goal is to get to zero cards very quickly. Lots of little threats that are lighter on mana. This lets you draw a lot more action if the game stalls out. The
Pack Rat provides a way to self-discard to keep the
Scrivener active if you draw multiple lands.
With the addition of the mutavaults, I'm not 100% sold on the Shred-Freak being in. We'll have to see. There are certainly other options around that spot, most notable here would be
Agent of the Fates for it's defensive abilities, if needed, while getting Pack Rats online if that's your plan (same goes for Thrill-Kill).