BeholderBurger said:
I thought that , to use a Special attack, you needed to first fulfil the criteria i.e. with smite good you would need to know that the creature is good. Now if a creature has the ability but has no way of determining that the enemies alignment is good then how could they ever use such an ability.
In the Smite Evil Paladin's ability description it indeed says he can use it agains a non-evil creature, and the daily use goes wasted. I think it was written exactly for the case when the Paladin is not sure if the foe is evil, but wants to try anyway the Smite Evil.
BeholderBurger said:
How could I use this ability without unrealistically targetting the good players and yet not undermining the only good ability of an abyssal rat.
Together with the other good suggestions in this thread, you may also consider the monster/NPC to use his Smite Evil just as any PC uses an ability when he doesn't know if the foe may be immune: they may wait to get a clue, or just try before it's too late to use it. If your monster has Int 3, at most you can make it wait until he feels in greater danger (e.g. after he gets the first hit, or when he's below 50% HP), then use it against the PC who just hit him. Or just use it as first attack, against the closest PC.
If you find yourself in a situation where the monster may target 2 or more different PCs, you (DM) know who is a better target but the monster itself does not, don't be afraid to roll randomly.* After all, that's what also players do sometimes

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BTW, I do the same as a player (Cleric): if 2 friends are dying, and I fail a Heal check to know who's closer to death, I roll a dice to decide who I heal first. I don't like abusing the fact I know exactly how many negative points they have.
*but more easily you can go for the closest PC
