Under $10: Cryptbreaker, Zombie Master (if you're adding Urborg, Tomb of Yawgmoth), Balthor the Defiled, Crypt Ghast, Graveborn Muse, Grimgrin, Corpse-Born, Living Death, Dimir Signet, Beseech the Queen Pricey stuff: Sidisi, Undead Vizier, Relentless Dead, Lord of the Undead, The Scarab God, Mikaeus, the Unhallowed, Phyrexian Altar, Yawgmoth's Will, Vampiric Tutor, Demonic Tutor, Intuition, Cyclonic Rift, Tombstone Stairwell, dual lands, fetches, you know the stuff If you want to enhance your finisher potential even further, then adding Phyrexian Altar makes your Gravecrawler combos much more powerful, but that's a $70 investment
Cards like Thought Monitor and Urza, Lord High Artificer provide resources for the midgame, until Cyberdrive Awakener and Tangletrove Kelp close things out
This trend in quality difference continues throughout the entire deck
THE BUFFS These cards don't see a lot of play in EDH, at least from the groups I've been involved in
Workshop Assistant - 2 Gets better the more the artifacts we get into Standard
The only reason it sits at three rather than the top is that it is yet to fully find its ideal setting