I wanted to create a voice similar to a Chaos/Death Knight. I didn't want just audio though I wanted to build a scene with marching undead and crows and undead dragons and the like. I created the audio of the zombies by recording myself numerous times and combining the tracks, then I followed it up with some audio effects to make it sound more undeath like; more soul trapped in a husk that's non-wilfully marching. I took inspiration from World of Warcraft's Deathknight class and other game's necromancy like classes. I hope you enjoy it!

Credits (Sound SFX):
Freesound.org
Horse Whinny, Close, A.wav" by InspectorJ (www.jshaw.co.uk) of Freesound.org