This is my actual unblockable/aggro mono-green deck. It is offensive, quick and has low mana cost. I play with it in my circle of friends, obtaining some wins (most against other aggro decks since they usually don't contain a lot of removals).
My best-case strategy:
Turn 1: Forest -- Nothing else to do.
Turn 2: Forest. Strangleroot Geist for a quick damage with haste. (count as a defensive creature too since it has undying);or
Wandering Wolf
. or
Skinshifter
Turn 3: Forest. Wild Beastmaster.
Turn 4: Forest. Now you can use your forests to give power to Wild Beastmaster with Vines of Vastwood and/or
Primal Bellow
and/or
Blanchwood Armor
.
Note that you can use
Wild Defiance
to boost your growth cards effect.
As I said, this deck is most offensive but you can use Fog to prevent inconvenient combat damages, or use Predator Ooze's indestructible hability and the
Skinshifter
's transformations to block.
The weak point is that it depends too much of having creatures in battlefield, otherwise it won't be able to do damage, that is the main goal of the deck. I recently changed
Titanic Growth
for Vines of Vastwood because the second do the same thing but give hexproof as well, helping against Doom Blades, Lightning Bolts, etc.
Suggestions/critics are welcome. :)