While a lot of players are still trying to finish Blackrock Foundry, the ones who've completed it on the hardest difficulty are already looking for new challenges. Like Kief and his friends, who tried to do the 10-man version with only five players in the group, just like a normal dungeon.
They killed 9 out of 10 bosses during their run on normal difficulty, including Blast Furnace, a very hard encounter right before the final boss. And they even managed to down the final boss Blackhand to 15 per cent. The raid has three difficulties: normal, heroic and mythic, and each difficulty scales depending on how many players join the group. But it never scales below the 10-man mark.
Here's a video of the 5-man team's Blast Furnace run for proof (with an extra Swedish language lesson). According to them they had an average item level of 695, which is... very high. Just for comparison, you start in Draenor with around 485 and you need 635 to be able to enter Blackrock Foundry.
That's a pretty neat achievement considering that Blackrock Foundry is not some easy-to-solo old raid and we're not even close to a new expansion, when fun runs like this mostly happen (remember those 5-man Karazhan runs?). It's the current top one, only out for a couple of weeks and still only beaten by a few dozen guilds on the hardest, "mythic" difficulty.