Ear worms are tiny insect larvae found in old wood. In order to mature into their adult insect form (a kind of large fly, according to sages), they must eat meat, burrowing through it as they do through wood. They are particularly attracted to the various orifices of animals and humanoids; they are not specifically fond of ears, but were so named because of their propensity for traveling from decrepit dungeon doors into the ears of adventurers listening at them.

If any living creature makes prolonged contact with an infested wooden object or structure (at least one combat round), up to 1d8+8 of them will enter the creature, preferably via an orifice, but if necessary they will puncture the skin. They secrete a numbing agent that prevents the victim from feeling their presence. The larvae will eat away at the victim slowly, but as they move inward they will cause 1 point of damage every hour for each larva. The larva mature in 4d6 hours, at which point they move to the skin surface en-masse, doing an additional 1 point of damage each before emerging in their final form and flying off to mate and then find some rotten wood in which to lay their eggs.

While the victim does not generally feel the larvae entering their body, there may be other side effects that might tend to reveal the infestation. Those making entry through exposed skin, for example, will leave a scattering of tiny holes dotted with blood. Individuals who were infested by way of the ear sometimes report hearing distant music, chanting, or singing, never clear enough to be understood; this effect generally lasts until the larvae undergo their final transformation and leave the victim’s body (or are killed somehow, as described below).

There are several possible ways to cure a character or creature infested with ear worms. First, and easiest, is to cure disease, which will instantly kill all larvae infesting a creature. Drinking a poison potion is another method; whoever drinks the poison must, of course, save vs. Poison or die, but so must the larvae. Area-effect spells (such as fireball) do full damage to the victim but only half damage to the larvae; consider the entire group of larvae as a unit, where each point of damage kills one of them, and any remaining thereafter continue to damage the victim. The referee may choose to allow other methods of killing the larvae; players are counseled to be creative.