Cyclops

Cyclopses are a species of giant defined by possessing only a single eye. They are physically stronger and have a higher constitution compared to Hill Giants, but are equally deficient in intelligence, wisdom, and charisma. They use no weapons, relying on their brute force fists to crush their enemies.
Only a single cyclops is encountered in the entirety of the Baldur's Gate trilogy. He can be found in front of the gate to the Underground River Entrance, along with seven other crusaders (five are visible and two are hidden), during the Siege of Dragonspear campaign.
If your thief pickpockets the Seal of Caelar off of him and then you show it to him during the dialogue, he'll let the party into the entrance to the underground river without having to fight their way in.
==Dialogue==
You not go here. This secret place.
:And a fine secret it is. However, I really must get past you.
Me crusader. You not look like crusader. You go 'way, me stay here and guard.
:I serve the Lady even as you do. See here, I have her seal.
Where you get that?
:I required it on my mission for the Lady. I can't share the details—you understand.
Then you crusade like me. We friends. You pass.