20 cards where the color identity ≤ BW and the card types include “zombie” and the card types include “legend”

Mikaeus, the Unhallowed (Commander Masters #173)
Sidisi, Undead Vizier (Dragons of Tarkir #120)
Ratadrabik of Urborg (Dominaria United #213)
God-Eternal Oketra (War of the Spark #16)
Tormod, the Desecrator (Commander Legends #155)
God-Eternal Bontu (War of the Spark #92)
Acererak the Archlich (Adventures in the Forgotten Realms #87)
Ebondeath, Dracolich (Adventures in the Forgotten Realms #100)
Geth, Lord of the Vault (Double Masters #94)
Josu Vess, Lich Knight (March of the Machine Commander #253)
Haakon, Stromgald Scourge (March of the Machine Commander #252)
Daxos the Returned (Commander 2015 #43)
Balthor the Defiled (Judgment #61)
Gorex, the Tombshell (Commander Masters #164)
Vogar, Necropolis Tyrant (Game Night: Free-for-All #3)
Hancock, Ghoulish Mayor (Fallout #45)
Korlash, Heir to Blackblade (Future Sight #87)
Geth, Thane of Contracts (Phyrexia: All Will Be One #95)
A-Acererak the Archlich (Adventures in the Forgotten Realms #A-87)
Vladimir and Godfrey (Alchemy Horizons: Baldur's Gate #32)

Though this query has ended, its relics still slumber in New Argive.