They had been left 'alive' by both the Awakener Association and the Titans, as these creatures acted as a natural barrier, preventing anyone from entering the Savage Expanse without resistance.
Neo dealt with the monsters swiftly.
His sword cut through the zombies with ease, the corrupted flesh falling apart with each strike.
While both were undead types and contained large amounts of Death, zombies were weaker than skeleton monsters.
Zombies had flesh bodies, which signified the presence of Life elementals.
Even Neo, despite his lack of Life affinity, had Life elementals within him because he was 'alive.'
Skeleton monsters, on the other hand, had no flesh, organs, or anything that connected them to the living.
They were wholly composed of Death elementals, making them more powerful.
...
Broome, Australia, Shadow World
The blazing sun hung high over the arid desert landscape of Broome.