Down Goes Van Rook

The NPC you have to kill is a reference to Elliott Venczel who in-game is referred to as Venruki or shortened Ven. (Elliot obviously in reference to his first name, and Van Rook in reference to Venruki). Venruki is THE most accomplished mage in WoW history; he has won tournaments like Blizzcon and MLG and also having received rank 1 titles from numerous PvP seasons in each and every expansion.

As for the achievement, it's not only a reference to Venruki, it's also a reference to one of my favorite clips of all time and memories from WoW as a whole, namely this video, which is a clip from an old WoW arena tournament (MLG Orlando, 2009) in which he got damaged and eventually killed so fast he couldn't even react to it, and so he died without using his Ice Block.

"Down Goes Venruki" is a very common phrase yet to this day. And you know he'll hear about it every time he dies without Ice Blocking. Hell, he hears it every time he dies even when doing close to zero mistakes including using his Ice Blocks.

Of course it's not entirely his fault as the damage back then was a lot higher relative to the health and not only could the reaction time be a factor but if you triggered the global cooldown in the wrong moment you would be dead, as likely is the case here.

Venruki also streams occasionally on twitch.tv and you can check that out if you want to watch high rated arena action and/or one of the best personalities on twitch. He has a decent viewerbase, but I definitely think he deserves more. He's a cool dude all around, and if you haven't heard about him or his stream before it's about time.

Sooo hordes got this achievement in their log, awkward.

I think this is the second reference to Venruki. First reference to him, was the item Venruki's Venerable Sash that dropped from Ordos.