Hi.

Can I use sentinel for Crazy Cob "when revealed" attack?

Crazy Cob
Type: Enemy
Encounter Set: Flies and Spiders
Threat Threshold: 30
Threat Strength: 2 Attack: 3 Defense: 2 Hit Points: 2
Creature. Spider.
Venom.
When Revealed: This enemy attacks the character with the most poison attached.
Shadow: Defending character gets 1 poison.

I don't see a reason why not.

Unless you're playing solo.

Doesn't the card specifically specify who the defender has to be? "The character with the most poison attached." So in that case you wouldn't be able to use a different character to defend.

Not true.

Cards that attack a specific target are resolved normally except that if they are left undefended then the damage must go on that target. (This is a very very weak effect since undefended attacks are quite rare).

So, anyone that could normally defend an attack could defend here (including any sentinel) and it would resolve normally.

Oh, wow, I have been playing this wrong for years. Found it in the FAQ:

(1.41) Attacks against a character

An attack made against a character works the same as an attack made against a player with one exception: undefended damage from an attack against a character must be assigned to that character.