Yeslick Orothiar

Yeslick Orothair is a Lawful Good dwarven Fighter / Cleric of the Orothair clan, who claimed the Cloakwood Mine as their home, until one of them breached the wall between them and the river, wiping out nearly the entire clan, almost a century ago. Yeslick was one of the survivors. He went to Sembia where he met Rieltar, eventually telling him of his old home. This proved to be a huge mistake, as Rieltar betrayed Yeslick and forced him to disclose the location of the mine. He has been imprisoned ever since, until the party attacks the Iron Throne operation site.

When he joins the party, he has no items in his inventory. He will leave the party if the mine is not flooded by the time fourteen days have passed. If he is taken to Candlekeep in chapter 6, there will be no additional dialog between him and Rieltar.

If upon meeting him the player declines his help, he will exit the map and can be found later in Jolapin's Tavern at the Baldur's Gate Docks

If the Yeslick accessed through the Console is any indication, then there is no particular advantage to recruiting him early. At Fighter 2, Cleric 3, the console Yeslick has 2 more HP than of the maximum possible HP, and at Fighter 4, Cleric 5, he has 1 more HP (and would save a lot of saving and reloading to keep that +2)

As a dwarf with 17 CON, Yeslick receives a -4 bonus to his saves against Death, Spells and Wands. He also gains +3 hp every fighter level and +2 hp every cleric level.

In-game biography
"When asked about his past, Yeslick quietly states that he was once a member of the dwarven clan Orothair. For generations they have used the iron mine in the center of the Cloakwood as their home, but almost a century ago, catastrophe struck. As skilled as they are underground, dwarves occasionally make mistakes. One such incident cost them dearly. They apparently breached an underground river and the resulting flood claimed nearly all of the clan. Yeslick was one of the few survivors, and made his way to Sembia to start a new life. There he made the acquaintance of Rieltar, a member of the Iron Throne, and was hired as a personal smith. They became friends, and eventually Yeslick told him of his past. This proved to be his undoing, as Rieltar used this information to formulate a plan to expand the Iron Throne power base in the Sword Coast. Rieltar betrayed his supposed friend and forced him to reveal the location of the mines. Yeslick has been imprisoned ever since so as not to reveal the site to others. Now he wishes for nothing but the chance to right the wrongs that have been committed using his ancestral home."

Quotes

 * "We do good, t'is as my clan was, long ago."
 * "When a dwarf says he is sick, you know it's serious!" (when critical health)
 * "Slow and steady while I'm leader. (when made leader)
 * "Ye need only ask."
 * "You need something?"
 * "What e're ye need."
 * "There will be dark horizons if we don't change our ways! (when reputation is low)
 * "Clangeddin's will be done."
 * "As you will."

Bugs
Yeslick's close relation to the Cloakwood Mines means that any bugs relating to that quest relate to him as well; the bug that caused him to complain that the mines were not flooded even though they were, was supposed to have been fixed in an early BG patch, but still exists in final version 1.3.5521.

There was a bug in BGEE that made him speak all the time, as you were right clicking him, making impossible to save the game and to move your characters. Also, he does not walk, and he did not fight, he speaks to the nearest party member. This however has been fixed.

Suppose Yeslick is recruited in the mines and is in the party when the mines are flooded. Then, if he is later dismissed from the party he will declare that the mines must be flooded to dampen the plans of the Iron Throne. Talk to him again and he says something to the effect of "bust some heads," but the recruitment dialogue is not initiated.

Strangely, talk to him yet again, and the recruitment dialog returns. Subsequent Yeslick dismissals get the "bust some heads" comment without any further mention of the mines.