By now, Scathe Zombies have been outclassed by the likes of Walking Corpse. Back in Alpha, though, creatures were different. A 2/2 Zombie for 2 in black would be pretty good. Now, I would want to make a 1/1 Zombie, but there's multiple Zombies depicted here. I couldn't have made this into a noncreature card because Zombie Master wants more than just Scavenging Ghoul to work with. So, either I keep this a 2/2 and add a small bonus, or I make it bigger. Obviously, I chose to make it larger.
However, I couldn't have made this creature too much larger. A 3/3 for 4 is too weak. And a 3/3 for 3 is too week. So, what do I do? I put a drawback on the creature. A flavorful one at that. Both Diregraf Ghoul and Rotting Legion exist with the "enters the battlefield tapped" drawback to evoke their slow zombie-ness. Here's a creature design that comes in-between!
I would have named it something that begins with "Shambling," (see Rotting Legion's flavor text) but it wouldn't fit between Sacrifice and Scavenging Ghoul, alphabetically. So I settled for Sauntering - not as wonderful, but it'll do. I chose to go with "Zombies" in the name instead of something else like "Corpses" or "Undead" because that would mean only Zombie Master would be the only Zombie in Alpha with "Zombie" in its name.