The Flames of the Burning Legion

Remember the Black Temple? Once the Temple of Karabor, this center of Draenei worship was defiled by the demon-blood-enraged Orcs in the earliest days of the Horde. When the Legion conquered Outland, Magtheridon the Pit Lord took the Black Temple as his seat of power. Later, Illidan Stormrage, now a half-demon thanks to the effects of the Skull of Gul'dan, conquered the Black Temple with the aid of Lady Vashj and Kael'thas Sunstrider, claiming lordship over Outland.

And then we showed up.

The Black Temple was meant to be the ultimate raid of the Burning Crusade, but it famously came out far too early (while most people were still working on tier 5: Tempest Keep and Serpentshrine Cavern,) and then remained the pinnacle of raiding for a very long time, until finally Sunwell Plateau was released in patch 2.4.

It was a very good raid, actually. Today, you'll probably only pass through Shadowmoon Valley for one level before heading off to Northrend, but the Black Temple was the "big ominous base for the big bad" like Icecrown Citadel was in Wrath (I guess Grommash Hold is that now...) I highly recommend running some old-school raids there for both the cool atmosphere and one of the best looking sets of raid tier armor they've made (special mention for the Druid and Paladin sets, though I know the Warrior, Priest, Rogue, and... well, they're all pretty good looking.)

But Burning Crusade effectively ended in late 2008, and BT has not been significant as an instance since then.

Until now.

It appears that on the 5.1 PTR, there's a new Scenario that takes you to the Black Temple. Specifically, I believe this Scenario is Warlock-only.

We've been teased before about the possibility of green fire (if you haven't checked out Shadowmoon Valley, take a look. The place is DEFINED by Fel Fire, altering various warlock abilities like Incinerate, Immolate, Rain of Fire and Soul Fire to have this look (though honestly, I think that given the changes to abilities, only Destruction's going to really change that much.) They had said they'd want warlocks to go through a quest chain to get this (not sure why it couldn't just be a minor glyph, but if we're getting all this I'm totally on board.)

Anyway, it apparently involves that Council of Six Daggers we heard about earlier, and harnessing some seriously powerful mojo. At Illidan's house.

The thing that excites me about this is the way that Scenarios allow Blizzard to use older parts of the world. Without going through the difficulty of building an entire dungeon or some such thing, they can instead take some pre-established area and have specific, controlled things occur within.

Expand on this, Blizzard. I would love to A: see some of the old class-specific quests, like the Paladin Charger chain, reimplemented, or the Battle of Undercity brought back in all its glory and B: Get a lot more content in the old world. We've heard about important events happening in major cities, like Moira's takeover of Ironforge, and we haven't been able to see them in-game. This is a great way to do this without the hassles of phasing.