Zombies shamble through the ruined streets of ravaged cities. Wraiths drift through the stonewoods. Wights rise from their tombs, hungry to slay. At present, there are probably more undead on Odekor than living people.
When the godstorms swept through creation, the delicate process of death was disrupted. Previously, when a living being perished, psychopomps in the service of Eligel would escort them to their final destination, either the Fields of Joy or the Plains of Agony. Now, when someone dies, their soul is vulnerable. Psychopomps do not come to escort the departed away from the Material Plane. Rather, the departed must set out on their own, to find their own afterlife. Those who linger in the Material World too long can become undead.
The prevention of physical undead, like zombies and wights is fairly easy. You simply burn the body.
Spiritual undead, however, are more difficult to prevent. Wraiths and spectres haunt the five continents, seeking to extinguish all life. Its possible they would have done so already if their undead natures had not been altered by the godstorms.
Sunlight damages and can destroy a wraith or a spectre. Wights have never cared for the light of day, but now they flee it to preserve their existence. (In game terms, most undead lose half their hit points if they start a turn in sunlight, and they do not get any sort of regeneration while they remain in the light.)
Only zombies do not take damage from exposure to sunlight. Indeed, Odekor zombies are difficult to destroy. The world is drenched in necrotic energies, so that if a damaged zombie does not lose all of its hit points, after eight hours it regain its original hit points. Because of this, when facing zombies, adventurers know to ensure their destruction.
Of course, not everyone becomes undead. Most of the deceased gravitate naturally toward their intended destination. Some find unexpected help on the Dead Roads from those who have gone before them.
Wizards, oracles and seers exploring the afterworld, have spoken of a rumored city called Torin, made all of glowing white stone, standing on a bone shore next to a black sea. Here, they say, the Dead Gods reside in cold splendor, with their fallen armies. Fresh souls are welcome in Torin, where they can reside for as long as they wish, before continuing on to the Fields of Joy or the Plains of Agony. Whether this is true or not is anyone’s guess, but most are skeptical.