Stands for Killing Service, Inc. One of the top elite Halo 2 clans. Many branches include KSI Firewall, KSI Power, etcetera etcetera. Has strong competition with MLG.
by Squiz May 30, 2006

A once toxic gay clan on halo to a black nigga man from the sdmn. anyone who holds ksi in their name in halo is now a Ksi fan
by shadownigger October 1, 2019

by Keele Beb April 16, 2009

by big daddy long slong October 24, 2019

by Rambothegambo February 2, 2020

Best youtuber on the planet by far and did the world a favour by making the pauls his bitches he is a mighty character stronger than thanos himself!!!!!!
by Backa665 October 22, 2018

by thetruetellerofWARDS October 19, 2018
