Black Zombie Deck

Hi everyone. I'm relatively new to magic, so any advice you can give me would be great. This is the deck I've been working on so far:

23X Swamp

4X Diregraf Ghoul
4X Walking Corpse
4X Cemetery Reaper
3X Skinrender
3X Vengeful Pharaoh
2X Geth, Lord of the Vault

4X Call to the Grave
3X Endless Ranks of the Dead
3X Nim Deathmantle
2X Caged Sun
4X Ghoulcaller's Chant
1X Army of the Damned

So far I have stayed away from blue because I haven't decided whether I like rooftop storm enough, and I dislike blue zombies needing to exile creatures which I could be making into more zombies.  That doesn't mean I am not willing to try blue, however.

Finally, I've thought about cards like Grimoire of the Dead and Army of the Damned, but wasn't sure if I needed any of them.  Any advice would be greatly appreciated.  Thanks.

This is a pretty good Zombie deck. I would add more Skinrenders and maybe a Ghoulraiser. I like Ghoulcaller's Chant as well.

Moan of the Unhallowed and Army of the Damned seem good.

Army of the dammed is good maybe just 1 or 2 as your finish card but I would take it out against any red deck that play pyro or slagstorm

Thanks for the advice.  I was thinking about removing 1 swamp, 1 Endless Ranks of the Dead, 1 Caged Sun, and 2 Decimator Webs.

Then I would put in 4 Ghoulcaller's Chants, mainly with the purpose of saving Cemetery Reaper and reusing Skinrender, and I would also add 1 Army of the Damned.

Does that sound good, or should I change this?  Thanks.

Grave titan

I have actually thought about Grave Titan since it is an awesome card, but I have to get a Nim Deathmantle out first, so if I don't or it gets destroyed then he is pretty much dead thanks to Call to the Grave.  Is it worth the risk?

In my opinion yea just for his ability personally I put hexproofing cards in my deck to keep him alive

Yeah I might put one in because you're right about his ability being good.  The only problem is that hexproofing wouldn't save him because Call to the Grave is an enchantment that I control and it's not targeting anything anyways.

Oh well, he's probably worth it.

He's strong with a good ability

Also, find a better two-drop. Walking Corpse just sucks. I've playtested it.

Ok I agree Walking Corpse is useless but I don't know of any other zombies for 2 mana to take it's place.
Any suggestions?

Depending on the format, Withered Wretch is functional. Especially with the gy interaction in Innistrad.

Ok, but I don't see how that would help, since I want to turn their creatures into zombies and bring mine back. How would it benefit me? Sorry, but I honestly don't understand.

What about Grimoire of the Dead?

Well, Weatherman, the wretch is a 2/2 for 2cc that can get rid of problems like flashback cards and is strictly better as a two drop than Walking Corpse.  I don't actually see any cards in your list that are bringing anything back from your graveyard except the Vengeful Pharaoh, and he basically brings himself back.