Somewhere else I said the goblins might be corrupted halflings. But there might be different kinds of goblins, not all of them little green men. Here are couple.
AC 12, HD 4, 18 hp, MOV 90′ (30′), ML 9, #ATT 1 tentacle or 1 projectile or fusion, DMG 1d6 or 1d6 or special
A bloody mass of tissue, vaguely humanoid in shape, as though someone had inverted a small person inside out.
Tentacle (mêlée). One per round, the hemogoblin can produce a metre-long tentacle that executes a swift whip attack for 1d6 damage.
Projectile (range). One per round, it can squirt acidic blood up to a distance of 10m, 20m with a -2 penalty, or 30m with a -4 penalty, for 1d6 damage.
Fusion. It tries to hold on to its opponent (mêlée roll; no damage). If successful, it will immobilize it for one round, and in its next action the hemogoblin will try to enter its victim through any hole it can (victim saves vs. Paralyzation to avoid it).
Once the hemogoblin is inside the host, it will remain dormant for some time, and at the most inopportune moment, its presence will prevent the host from having full control of its body.
Mechanically, this translates into penalties to their action or salvation rolls.
And when the referee sees fit, perhaps a few weeks later, the hemoboglin will hatch: the host body will throw hundreds of tiny hemogoblin larvae in the form of blood clots through the mouth, eyes, nose, etc., suffering a massive 6d6 damage.
History Hook: PCs have been hired to lead a hemoglobin-infected person to where a healer can have a cure. You have to get there before the hemogoblin hatches.
AC 12, HD 1, 5 hp, MOV 90′ (30′), ML 9, #ATT 1 weapon or 1 command, DMG as weapon or special
These creatures have the proportions of a human being, but their height is about one meter. Their heads are shaped like planets and are believed to come from the stars.
Weapon (range). Cosmic goblins usually carry a strange device that shoots a musical beam of silvery light at a distance of 20m, 40m with a -2 penalty, or 100m with a -4 penalty, causing 1d8 damage.
Command. One per battle, the cosmic goblin can insert a mental command into an enemy, ordering him to carry out an attack against whomever the goblin says. This action is undetectable; whoever has received the command is not aware that he has acted on the orders of the goblin, he simply does not know why he has attacked a companion (or whoever it was). To avoid this, the victim must save vs. Magic.