Dies to Removal

I think you had a really solid BG list. I think I would have tried something like

[deck]
Creatures (15)
1 Satyr Wayfinder
2 Venom Sliver
1 Invasive Species
1 Gargoyle Sentinel
2 Netcaster Spider
1 Witch's Familiar
1 Gravedigger
1 Living Totem
1 Zof Shade
2 Shadowcloak Vampire
1 Genesis Hydra
1 Siege Wurm

Spells (6)
1 Sign in Blood
2 Hunt the Weak
2 Flesh to Dust
1 Endless Obedience

Planeswalkers (1)
1 Garruk, Apex Predator

Land (18)
9 Swamp
8 Forest
1 Llanowar Wastes
[/deck]

You pulled a lot of great ETB creatures in Satyr Wayfinder, Gravedigger, Living Totem, and Genesis Hydra for Invasive Species to get value out of. Gravedigger + Endless Obedience lets you get your non-Garruk bombs back or hell, just 1/1 deathtouchers. I like Zof Shade more than I probably should, but I have a soft spot for mana sinks. 18 land may be unnecessary, but with a 7 drop and a fairly heavy top end plus
Genesis Hydra, I thought that hitting land drops would be more important than usual.

The Hunt the Weaks may be too weak for this deck. A lot of the deck is stall with X/3's but fighting your deathtouchers could be good enough.

inb4 Madding drops knowledge bombs all over my shit.