A fitting topic for a dead blog, right?
The undead mostly blow in D&D. This comes from the fact that all the undead tropes are familiar to players, both in style and mechanics. So no one is afraid of the undead and everyone knows how to leverage their strengths and weaknesses. Let's change that up a bit.
The undead have to be shrouded in the unknown in order to invoke any fear in the players. This means much more than just shuffling their abilities around or contriving new strengths and vulnerabilities for them. On a fundamental level, we have to strip the Cleric's ability to trivialize the undead. Then, we have to strip in-game and meta-game knowledge about the undead. From there, we can build undead foes while sprinkling in some of the (ir)rational fears that we share as people.
Let's take up that second item here with a look at zombies in the 17th century. All undead need to have some sort of 'fear aura' that eliminates the 'undead hunter' trope. You know, the expert in killing undead, of which there is invariably one hanging out in each town. Nearly every encounter with the undead should result in death or fear in order to maintain the milieu.
No. Encountered: Varies
Armor Class: 8
Hit Dice: 2 (d8)
Special Attacks: Putrefaction
Special Defenses: Fear of the Grave, Undead Resistances
Save: Fighter 2
Zombies are the manifestation of the fear of the grave. They are walking corpses who carry the stench of death with them. Zombies can be deliberately created by malevolent forces or arise from those who have not been properly buried and consecrated.
Zombies exude a Fear of the Grave upon all who behold them. All must pass a morale check or Wisdom saving throw or flee in terror.
The touch of a zombie causes instant Putrefaction to living flesh. These wounds fester with disease and heal at a severely reduced rate. Putrefaction wounds only heal at the rate of 1 per day of bed rest and only upon a successful Constitution saving throw; upon a failed saving throw, roll for the contraction of disease. Magical healing has its full, normal effect upon Putrefaction wounds.
All undead are immune to charms, enchantments, sleep, and hold spells.
Zombies provide us with a template for the undead. All undead will have some sort of aura that plays upon a human fear and requires a type of saving throw or morale roll (these will vary with undead type). There will still be a shuffling of strength and vulnerabilities as a necessity, but I will strive to keep it fresh and new.
The design intention here is that these two items will make encounters with the undead uncertain and prevent the players/characters from building upon a knowledge base that ultimately trivializes the undead.