Here's an appropriate April Fool's Day character class, inspired a little by the Judges Guild Buffoon class, but mostly by the simpleton in traditional folk tales. There's a touch of my tourist class as well.
FoolConcept: Character who gets by on dumb luck instead of skill.
Alignment: Any, although Law and Neutral predominate.
XP/HD: As Fighter, but their prime ability is Wisdom. Invert the experience bonus for Wisdom: they have an XP penalty for high Wisdom, a bonus for low Wisdom.
Weaponry and Armor: No armor restrictions, but has no skill with long-range weapons (bows and crossbows) or with weapons based on mechanical devices.
Limitations: Always surprised in combat. Can't disbelieve illusions (Phantasmal Forces won't vanish when touched by a Fool) and believes everything they're told (no chance of detecting lies, although another character can tell a Fool that something is a lie.) If some kind of training rules for learning languages or new abilities are being used, Fools take twice as long to learn something new.
Other Abilities: Can befriend animals or fairy creatures to have them perform one task (treat as Turn Undead roll.) Save versus anything other than charm or illusion as if four levels higher. Reaction rolls are at +2, and no creature has an automatic Hostile reaction to a Fool, not even the undead.