half elf racism.

GHOUL These are evil undead creatures whose touch alone is known to
paralyze a man. They feed on corpses and attack all living things on
sight. Characters hit by ghouls (elves excluded) must save or be
paralyzed.

Ghouls paralyze any normal character that they touch, except for elves. They otherwise melee in the regular fashion and are subject to missile fire. Any man-type killed by a ghoul becomes one.

3rd edition agrees actually.

Ghoul CR 1; Medium Undead (5 ft tall); HD 2d12; hp 13; Init +2 (Dex); Spd 30 ft;
AC 14 (+2 Dex, +2 natural); Attack +3 melee (1d6+1 and paralysis, bite),
+0 melee (1d3 [x2] and paralysis, claws; SA paralysis, create spawn; SQ undead; AL CE; SV Fort +0, Refl +2, Will +5; Str 13, Dex 15, Con --, Int 13, Wis 14, Cha 16.
Skills: Climb +6, Escape Artist +7, Hide +7, Intuit Direction +3, Jump +6, Listen +7, Move Silently +7, Search +6, Spot +7. Feats: Multi-attack, Weapon Finesse (bite).
SA—Paralysis (Ex): Those hit by claw or bite attack must succeed at Fortitude saving throw (DC 14) or be paralyzed for 1d6+2 minutes. Elves are immune to this paralysis.
SA—Create Spawn (Su): PCs killed are left to rot for 1d4 days, after which time they rise as undead of similar type as those who killed them. Casting a bless spell on the body before the end of that time avoids the transformation.
SQ—Undead: Immune to mind-influencing effects, poison, sleep, paralysis, stunning, and disease. Not subject to critical hits, subdual, ability damage, energy drain, or death from massive damage.