This began as just me wanting a list of all the zombie creatures, specifically, all the older zombies. Then when looking at the list, I thought, "why not make a commander deck from the list?" And viola. First, I had a list that went from Alpha through the Invasion block, there's enough good zeds in that mix to make a fine commander deck, even taking out those with non-black color abilities. The choice to extend into the Odyssey & Onslaught blocks was not taken lightly, both of those cycles are VERY heavy tribal themed, the Onslaught expansion alone has TWENTY-ONE zombies! So expanding out to the Pre-Mirrodin line gave me a HUGE list of zombies to start with, which I need to pair down to a playable 100 card deck. I have already removed the handful of black zombies with non-black abilities (Balduvian Dead, Nightscape Familiar, Mournful ZOmbie, Quagmire Druid, etc) as well as a few whose abilities were tied with themes that didn't fit the deck (snow covered lands, clerics, shadow creatures). Now I just need to whittle the 88 cards listed down to 60-75, and add appropriate land. I have already decided to NOT include other spells (instants, sorceries, enchantments & artifacts) as they will 1) clutter the deck up, and 2) take away from the sheer volume of zombies. Besides, between the abilities of these zombies (many of which duplicate powerful enchantments and instants) and the number of abilities that tie into "creatures" (as opposed to non-creature spells), a creature horde, or to be more appropriate, zombie horde, seemed to fit the theme better.
All the creatures listed are zombies, despite what their card says. I intentionally selected the earliest printing of the cards, going back to Revised, so quite a few weren't zombies when they were originally printed. Two of the cards aren't listed as zombies on this site, but I see no reason NOT to include them as zombies (making a judgment call on this one), 1) Khabal Ghoul...every ghoul that's ever been released by MTG is now a zombie, so this seemed to be a no-brainer to me, despite the odd skeletal artwork of the card (for those that think it may have to do with some sort of an Middle-Eastern translation variation, I point you to Cyclopean Mummy, which this site lists as a Zombie...to me, a Mummy and Zombie aren't the same, but if you're willing to call a Mummy a Zombie, then what reason could you possibly use to not do the same for the Khabal Ghoul?); 2) Walking Dead is listed as Undead...sorry, but using modern parlance, "walking dead" is probably the most synonymous term for "zombie", even more than "ghoul" which is more often closer affiliated with "vampire", so as far as I'm concerned, it's a zombie.
The six cards on the Sideboard are all potential Commander's for the deck. It's very hard to find a viable Legendary Zombie that is also pre-Mirrodin. The ones that do exist, that are mono-black, have abilities that are tied to Minions, Thrulls, Nightmares or Knights that would be less than useless in a zombie deck. The ones listed here fill at least one criterion, each is a Legend. But, each has at least one thing that makes it a bad fit.
#1 Gallowbraid is era appropriate, but technically isn't a zombie...though he does look like one (I'd ask for a DCI/Wizards call on this one, his partner Morinfen is obviously a feral vampire or maybe a demon, Gallowbraid has to be a zombie, right?). He doesn't have a great ability, just trample, and when you tire of paying his upkeep, just return him to the summoning zone and re-cast him. Works, but not a great fit.
#2 Phage, in her several printings, she's never been labled as a zombie, yet THIS site lists her as a Legendary Minion Zombie (?), she is era appropriate and has a nice ability, but I'm not sure she fits the "Zombie" theme. Personally, I wouldn't use her in a commander game, because her ability to eliminate players would circumvent the Commander rules (though technically isn't illegal), and would ruin the fun of the multi-player game.
#3 Lim-Dul, this card came out with Timespiral, so he's not era appropriate, BUT, his name is splattered across several old-school zombies, so I'm okay letting that slide. As a necromancer, he fits the zombie theme nicely and his ability to convert dying enemy creatures to zombies under your control, makes him a very nice commander. Lim-Dul would be my FIRST choice as a commander for this deck.
#4 Geth, Mikaeus & Gisa, all three are recently released cards so none fit the era requirement. All three are very thematically appropriate though: Geth IS a zombie, as is Mikaeus (also a cleric); Gisa is a wizard (read Necromancer) with zombie-themed ability. If you're willing to fudge the era theme for the commander, any of these three would make EXCELLENT zombie commanders.
EDIT: I pulled some cards off the main list and put them on the sideboard. Since this deck has very few ways of gaining life, I thought Deepwood Ghoul, Gangrenous Zombies, Wretched Anurid and Zombie Cutthroat were..."security risks", their ability life costs were just too steep, I don't think I'd want them. I also set aside the Phyrexians (including Order of Yawgmoth & Sanguine Guard), since they aren't traditional zombies...I haven't ruled out using them, but pulling them would be easy and drop the casting cost quite a bit, since most are fairly high-cost, but I didn't want to delete them...better to set them on the sideboard until I decide their final fate.
EDIT: Pulled Anurid Muckdiver, Dripping Dead, Zombie Assasin and Fallen Cleric (now on sideboard). Three high-casting cost creatures I don't think are worth the cost, though if I knew I was playing someone using black, I'd probably put Anurid back in the deck to take advantage of its swampwalking ability.
At 105 cards (now including land), I just need to trim 5 more...the bell curve is pretty nice, might need to trim some 3 & 4 casting cost spells now, that should about do it.
1) Pulled Rank and File - good card against a green Saproling or Elf deck, so it makes for a good sideboard card. 2) Pulled Smokespew Invoker - I always hate high ability casting costs, 8 mana just for a -3/-3 seems pretty steep to me. 3) Pulled Dread Wight - I like it's ability to paralyze, but then I thought about it...any creature with a toughness 3 or less, would just be killed by the Wight, and any creature with a strength 4 or greater would kill the Wight...which only leaves creatures with strengths between 0-3 and toughness between 4-X that would suffer the paralysis effect...not really worth the 5 casting cost IMO. 4) Pulled Organ Grinder, not a bad card, but exiling 3 of my graveyard zombies just to do 3 points of direct damage seems pretty steep. 5) Last one...I pulled Coffin Puppets, high cost, expensive ability...not a bad card, but I had to make a cut.