Herald of the Dreadhorde is a common Creature — Zombie Warrior card from War of the Spark (WAR), collector number 93. Current market price: $0.09 (foil $0.39), TCGplayer market prices via Scryfall.
When this creature dies, amass Zombies 2. (Put two +1/+1 counters on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)