Kivan and Tazok

This companion quest only exists in Enhanced Edition of the game, in original version of Baldur's Gate, Kivan will stay in the party no matter how long it takes the player to reach the Bandit Camp.
This companion quest starts as soon as Kivan joins the party. As it's earliest available from Chapter One but can't actually be completed until Chapter Four, it's advised to time your progress or Kivan leaves if you take too long.
Kivan seeks revenge on Tazok, an Iron Throne leader in Bandit Camp. Finish the main story of Chapter Three, then report back to Officer Vai in Beregost will mark this quest complete, it's safe to do so with Kivan in party or not. Your report will also flag Kivan to be a potential permanent party member if you haven't recruited him yet.
As of at least v2.1.17.0 of the enhanced edition, the quest is marked completed as soon as chapter 3 is completed (taking the notes from chest). No trip to Officer Vai is required.
Kivan will leave by himself when the timer is up, with the length of the timer depending on when you first recruited him (20 days if you recruited him in Chapter 1, 14 days in Chapter 2, and 3 days in Chapter 3).
When Kivan reminds you for the first time about your promise to find the bandits, a variable is set: if you haven't visited the bandit camp after five days, he will leave.
==Journal==
Prior to BG:EE v2, the companion quest Kivan and Tazok appears not in the Quests section of your Journal, but as a titled entry in the Journal section.
Start:
Upon completion:
If Kivan was present in the party during infiltration attempt: