Kill the Shi Emperor.

Kill the Shi Emperor is a quest in Fallout 2.

Overview
If you choose to be a Hubologist and follow their teachings, the assassination of the Shi Emperor is the First quest given by AHS-9, the Hub Leader (dressed in a tuxedo) or AHS-7, the recruiter (dressed in a dark purple tunic).

You have to go to the Shi Temple (west of San Francisco) and kill the Emperor (who actually is a super-computer that the Emperor's "advisor" uses to direct the Shi) by formatting "him".

Note: This is a very evil quest, because everyone in the city will attack you, so you'll have to kill everyone...

Detailed walkthrough
It appears, in the player character's favor that AHS-9 is not aware that the emperor is actually a computer, and killing Ken Lee will suffice to complete the quest. The most effective way to complete this quest is to use at least 13 super stimpacks on Ken Lee, wait for 10 minutes once you are outside his room and he will succumb to the adverse effects of the super stimpack without turning the whole town hostile towards you.