My original version of this deck was made during the Return to Ravinica expansion, with minor changes made until now.
With the release of fate reforged and Magic 2015 two cards made me rework the deck as primarily blue and green:
hornet's nest
and Archers' Parapet. I had originally felt pushed to red to get creatures that did damage on their own in Vent Sentinel and Lobber Crew
The goal of this deck is to get an infinite combo going with Axebane Guardian
+
Umbral Mantle
or Overgrown Battlement.
Once that infinite mana combo is up, the umbral mantle can be re-equipped to [[archer's parapet Lobber Crew or whichever creature is equipped with Viridian Longbow Thus allowing you to tap for damage and then untap with the mantle.
This can happen by turn 4 if lucky.
Drift of Phantasms is an amazing card for this deck, as it allows you to transmute it for any part of the combo you need, Axebane Guardian
+
Lobber Crew
+
Umbral Mantle
.
Bonded Fetch allows you to see more cards if for some reason your card just isn't coming.
Hornet Nest
+
Viridian Longbow
is just awesome. You hit the nest once, create a hornet, attach the bow then kill your opponent's creatures at will.
The original deck is http://tappedout.net/mtg-decks/04-02-15-infinitely-offensive-defenders/