Every Tuesday, Grantland’s Maester netw3rk, our resident expert in Game of Thrones lore (i.e., he’s “read the books”), will seek to answer lingering questions, untangle knotty backstories, and generally shine the light of Knowledge into Westeros’s darker corners. This week: precious steel, long-held grudges, and filthy cannibals. These learning sessions will be spoiler-free.

What’s the significance of the sword that Tywin had melted down and reforged into two blades? And what is Valyrian steel?

Let’s take this in reverse order. Valyria was the capital city of the Valyrian Freehold, a kingdom that once spanned a large swath of the eastern continent of Essos. It was the ancestral homeland of Targaryens. Valyria was known for two things: dragons and advanced, possibly magical, metallurgical techniques that produced weapons of uncommon strength and sharpness at a fraction of the weight of normally forged blades. Basically, Valyrian steel is the Game of Thrones version of adamantium, typed the incredibly sad nerd.

The proprietary nature of the Valyrian steel manufacturing process made the weapons incredibly expensive, but they were available. That is until about a century before Aegon’s Landing, when an as-of-yet undescribed catastrophe called “The Doom of Valyria” left the Freehold and its capital city a pile of variously smoldering and partially submerged — also possibly cursed — ruins. As a result, existing blades became essentially priceless, so Westerosi houses that had Valyrian blades guarded them jealously and named them after King Diamond songs (like Heartsbane, the Tarly family sword; and Longclaw, formerly of house Mormont until it was gifted to Jon Snow).

The Lannisters, of course, are famously wealthy owing to their rather conveniently located gold mines, and their Valyrian sword was named “Brightroar.” I say “was” because some centuries ago, one of the family’s more whimsical ancestors went on a sea journey, sword at his hip, and promptly vanished. Thus the wealthy-beyond-measure Lannisters were left wanting a thing that no amount of gold could possibly buy. It is, as the Maesters say, like rain on your wedding day. So, as you can imagine, Lord Tywin — ever mindful of status symbols — has been desperate to get a Valyrian blade back in the family.

Which brings us to “Ice,” the Valyrian steel greatsword of House Stark, which we first saw cleaving through the neck of an AWOL member of the Night’s Watch waaaay back in the first episode of Season 1, and, later, Ned’s neck in the penultimate episode of the same. Lord Tywin having the Stark familial blade melted down is pretty much the perfect metaphor for the Lannisters’ (seemingly) total root-and-branch destruction of the Starks. Tywin did not only annihilate the Wolves; that would be a waste. He had their strength dissolved and added to his own.

Knowing how the Lions love singing at weddings and whorehouses, perhaps they’ll eventually write a “Rains of Castamere”–esque song about it. They can call it “The Melting Ice.”

This Oberyn Martell fellow seems interesting! Now, who is he exactly and where is he from?

Oberyn “Red Viper” Martell is the rakish younger brother of Doran Martell, the Prince of Dorne and Lord of Sunspear. Dorne has an interesting history in relation to Westeros at large. It is the southernmost kingdom of Westeros and also the least populated, owing to its daunting geography and heat. The Red Mountains on Dorne’s northern border separate the kingdom from the Stormlands. Moving south, mountains and ravines become a vast desert, before finally giving way to a coastal greenbelt.

I like to think of Dorne as something like a combination of Andalusia and Afghanistan.

Aegon the Conqueror and his dragons managed to subdue all the kingdoms of Westeros except, that is, for Dorne. The Dornish, you see, are skilled guerilla fighters, and refused open battle, preferring hit-and-run raids and harrying attacks. Invading forces would have to navigate the easily defensible mountain passes, only to eventually be drawn into the deserts, their strength bled by Dornish ambushes and raids on their now stretched supply lines. Too much trouble, in other words, for not enough reward. It would be another 150 years, and eight Targaryen kings, before Dorne was finally subdued, and just as quickly as Dorne kneeled did it rise to its feet in rebellion. The ensuing war cost the Targaryens 40,000 soldiers and was inconclusive.

Am I supposed to remember that dude on the Night’s Watch Council who got all huffy when Jon snapped on his résumé as former commander of the King’s Landing City Watch?

That was Janos Slynt, the oily former member of the Small Council, most notable for being the dude tasked — in his capacity as commander of the City Watch — with carrying out Operation: Kill the Bastard Baratheon Babies. Tyrion, then Hand of the King, set about doing the non-Ned thing of surrounding himself with people he could trust. Janos — a creature of Cersei’s — most assuredly did not fit that bill. Thus did Tyrion have Janos sent to The Wall, where, it seems, he has risen rather quickly, as dedicated ass-kissers often do.

Why is Daario suddenly being played by the scuffling, annoying keyboard player from Treme? Also, who is he again?

Should I know the names Joffrey mentioned from the Kingsguard yearbook?

No. Well, maybe. Ser Duncan the Tall is an Easter egg callout of sorts for Song of Ice and Fire completists. He’s the main character in a series of short-story prequels set in the ASoIaF universe roughly 60 100 years before the events of the show, and a companion of Aegon V Targaryen, who was the brother of Maester Aemon of the Night’s Watch.

Ser Arthur Dayne is an interesting case. He was known as “The Sword of the Morning” and was one of the most accomplished and famous knights of his day. His role in the Kingsguard (I am now speaking as a book reader) kind of has to eventually be explored. That’s all I should really say about that.