Servants of Gla’aki

When someone is poisoned by Gla'aki, they become his undead slave, though still able to perform individual actions. At first they can still pass as their former self, but as time goes on, they become more corpse-like.

In the RPG...

There are four different outcomes of being hit by one of Gla'aki's spines: 

1) If the spine kills the victim and injects the toxin, they become a Servant of Gla'aki; 

2) If the spine kills the victim but they manage to break it off during the same round—the spine itself has 4 armour and 6 hit-points—then they simply die; 

3) If the spine fails to kill—there's only a 17% chance an average Investigator would survive—but the toxin is still released, then the victim becomes an undead horror, though not subject to Gla'aki's will; 

4) If it fails to kill and the victim manages to break the spine off, then they remain human. 

    

Once transformed, the victim's CON is multiplied by 2, and their DEX is divided by 3, otherwise their stats remain the same. Despite retaining their prior appearance when first turned, the wound left by the spine leaves a livid spot that does not bleed, and from which a network of red lines emanates. Over time their undead bodies start to decay, and after sixty years "the green decay" sets in, whereby they will decay almost instantly upon contact with sunlight.

In a video game...

I think the Servants of Gla'aki would be great in a video game. Assuming the gaping wound in their chest is hidden, they can initially pass as human, which could provide a nice twist for the player. Imagine being in a small town, interacting with all the NPCs, only to discover later that they're all Servants of Gla'aki, and are conspiring to make you one too.

In a film...

Gla'aki is a favourite of mine, and I'd love to see Ramsey Campbell's The Inhabitant of the Lake adapted to film.