2: Regenerate equipped creature.
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's black.
I'm pretty new to the game- and I know people seem not to like a lot of equipment, but I have been playing around with a corpsejack counter deck myself (haven't posted it here yet- just joined tappedout the other day), and the rings (Ring of Kalonia and Ring of Xathrid ) are pretty awesome, especially Ring of Kalonia (getting one of those on your oozes is nuts). Anyway, you can move them around cheaply and double-up on +1/+1s. Also, if you can splash just the tiniest bit of white, Mikaeus, the Lunarch is ridiculous for this deck. Fragile, but I have been playing around with two in my deck and even just having them out for a turn or two is great. Also (if you were to splash white), Gavony Township . I'm sure this is all obvious stuff and I haven't even finished reading the comments (so sorry if this is all repeated suggestion), but one never knows.
Anyway, nice deck. Gonna read the rest of your updates now.
Three things stick out to me.
You have to fight the temptation to stuff your deck full of spells at the expense of mana sources especially in EDH because the average casting cost is so much higher, so many of my suggestions will be to add ramp at the expense of more fun spells. After all, the only thing worse than drawing too many lands is not being able to cast the spells you already have. In EDH you also want to give more weight to the ceiling of a card rather than the floor. Blood Artist and Falkenrath Noble are very similar cards, but if you stick a Rancor or Ring of Xathrid on a Blood Artist he is still a little wimp, whereas Falkenrath Noble becomes a legitimate evasive threat. On to the suggestions in keeping with a primarily Standard-based card selection:
-2 Perilous Shadow too defensive.+3 Ravenous Rats nice rat, and fits perfect.-3 Deranged Assistant i don't think it fits in this deck. -1 Mental Agony too expensive. -1 card:Altar's Reap would prefer Think Twice . -1 card:Akroma's Memorial too expensive. -2 Amass the Components , -1 Mind Rot , +2 Think Twice pretty cool with Pack Rat . +1 Swamp , +2 Island , -2 Ring of Xathrid
You could have Balthor the Stout as Thorin Oakenshield. YOu could also have the rings from MAgic Core set 2012 be the rings from the books: Ring of Xathrid as the one ring. Or Rings of Brighthearth as it shows them in the fire, and it is from Lorwyn. Or Sol Ring . All of those could be used.
I like to use Ring of Xathrid for my Diregraf Captain to ensure he stays alive and to buff him. I run a similar deck. I understand you dont want anything higher than 5 mana, but may I suggest Mikaeus, the Unhallowed for the hell of it? It's nice to have and I used to sideboard him to counter fieldwipes. Making your creatures tougher and making it impervious to humans was really useful to me. I don't suggest Rooftop Storm . Every time I got it out my hand would be close to empty anyway and I wouldn't be able to put much out with him.
Guttersnipe won't do much with only 8 instants and sorceries. Your deck should be more streamlined; you could go for an exalted twist on the BR aggro decks that are around: you have Knight of Infamy , Tormented Soul would be fun, too.
The way I see it, you have two paths you can take with this deck: straight-out "hit them with everything", using lots of Rakdos Cackler s and other efficient, cheap creatures; or you go BR Exalted. The exalted version would give you a lot of room to shoot things with burn spells, but you suffer from a lack of hexproof for your guys; in this case Ring of Xathrid becomes effective; it regens from destroy effects and stops your auras from being destroyed.
If you think about it and tell me what you want the deck to do, I can help you more from there.
Nice build. However, I'm going to suggest Ring of Xathrid over Ring of Thune , or at least for use in conjunction with. The regeneration will protect your big 'un against most field wipes, and will also allow you to keep it after you throw down a Disciple of Bolas .