Basic Infect.

The new inclusions of Blossoming Defense in the main and Shapers' Sanctuary in the sideboard have made the UG infect build much more viable in the wake of the Gitaxian Probe ban and the influx of Death's Shadow oriented decks and the prevalence of Fatal Push

The goal here is to hit the opponent by turn 2 or 3.

Look for hands along the lines of Land, fetch land, Noble Hierarch, Glistener Elf, 2 +4/+4 pump spells and a Mutagenic Growth

A turn 2 win usually looks something like this:

T1: Land, Glistener ElfT2: Fetch land, double pump and Mutagenic Growth (win)

Now, the key to a T2 victory is Mutagenic Growth. It can make or break an early win and fuel a later Become Immense

Another key consideration is to view Vines of Vastwood, Blossoming Defense, and Apostle's Blessing as protection first, pump second. You have 10 options to protect your creatures in the case of a early removal.