The reason was simple. Blizzard instituted a new mode for 25-man dungeons called "Heroic" which was essentially a rehash of the same boss encounter, just more difficult. Bosses had new gimmicks which needed to be conquered in order to be able to say you conquered the "Heroic" version of the boss. This did not sit well with a bunch of people, including me. Shortly after our third or 4th Yogg'saron kill and several hours spent on working on a few Ulduar achievements (screw you, Lumberjacked), Still Life stopped raiding. Many of the members went on to join other guilds, some stopped raiding and played casually and others quit WoW entirely. I belonged in the latter group.
Through the second half of 2009 I opted to play Rift instead and leveled a Rogue to level 50. I also hit up FFXI one last time before putting it down forever. Although Blizzard released another raid - Trial of the Crusader - in August '09, it did not initially pull me in. Towards '09 I learned that Conquest stopped raiding and TI was a shadow of its former glory. What was Kilrogg without CQ and TI?
I came back to World of Warcraft to play in a guild called Nerv run by an ex-Still Life member. This guild was on the server Vek'nilash. I came back in November of '09 and aside from raiding with Nerv I decided to level a Paladin on Kilrogg as well. Just so happened that as I hit level 80 an old friend of mine, Chalae, sent me a very exciting in-game mail. No, not nudes.
End, Part 7