Some cards to consider adding: Desecration Demon , Reaper of the Wilds , Varolz, the Scar-Striped , Deathrite Shaman , Putrefy , Hero's Downfall . These are not in a particular order, but more good cards in general for golgari decks. Something to consider with this deck is that there are a few things that fill your graveyard(Jarad's Orders , Pack Rat , Grisly Salvage ) but scavenging ooze is the only creature capable of scavenging creatures without scavenge in the deck, and there are only two of him. I'm not saying retrieving creatures from the yard to your hand is bad, but there are easier ways to draw cards if that's what you're after (for example Read the Bones is a good one)Some cards that are not generally played are Down / Dirty , Jarad's Orders , and Pharika's Mender . I'm not saying they're bad, and there are other cards in here that are not commonly used, I'm just saying there's a reason some cards aren't played. I might just be rambling on now since I'm pretty tired, and I'm no expert so my opinion is not really worth anything, but do what you wish with it.

My good sir these are very helpful suggestions!! Thanks :) I am planning to use almost all of your suggestions as they are great. Again thanks

I agree with all comments and changes my good morrow hope to test this soon

I would Board the Reaper of the Wilds, its capable of handling a lot of what standard is offering right now, hex proofing to stay alive and death touching to clear threats.

Oh just thought of this as well. Instead of Grisly Salvage you can run Commune with the Gods incase you wanted to make sure you can free up black mana for anything else since it does the SAME thing just includes enchantments and cost 1G instead of BG.

Thankyou those are both great suggestions!!

I would personally remove all Slitherhead , as a free +1/+1 counter is okay, but not that impressive. I would also remove Down / Dirty , and sideboard the Doom Blade , as they will screw you so hard game 1 against black decks. Instead of the Blades, I would up Abrupt Decay to 4. Deathrite Shaman should probably be a 4 of in this deck, and I would buff Grisly Salvage to 4 as well. 24 land is the go to amount for most standard decks, and with this I would add two Swamp . Lastly, I would bring Desecration Demon to 4. Just to powerful to ignore, especially when you can scavenge it. Hope the deck works out for your friend. Tell him that original deck ideas are always the best.