Was doing the random dungeons and got Halls of Reflection come up (Third Instance for the new patch). As the lich king began to chase us we ran away like normal, and as i saw the wall spawn i decided to hit up my Swiftness Potion, i kept running at it expecting to hit it, but ran right through it before it had finished forming... after a quick lol i ran to the end to await my loots
So anyway, Hit swiftness pot as the wall spawns and dont stop running at it!
Also this is NOT to get your whole party past it.. it lets you walk by yourself to the end so you can go afk while the rest of them do the chase...