Episode 4 of Kill the Dragon, Michael Deering's December 2016 Minecraft Hardcore Challenge, picks up deep in the branch mine. Basket has enough diamonds for an enchanting table now. What's still missing is lava for obsidian. "I'm really surprised there isn't a lava lake already."
Lava at last
The tunnel keeps turning up iron and coal but no lava, and Basket starts to wonder about the time it's costing. "We have limited time, so this is also sort of a waste of valuable time." Then the wall opens on a small pool of lava with lapis in the stone around it. "Oh, there we go." The lapis comes along too: "lapis we'll need, that's good."
Basket switches to the diamond pickaxe and pours water over the pool, turning the lava into obsidian a few blocks at a time and mining it out. The bigger plan is taking shape. "We also could go into the Nether, it's another option too I guess." Blaze rods are on the list either way. "Wow, there's a lot of steps to get to the end."
A portal in the middle of nowhere
Instead of hauling everything home, Basket builds the portal right there in the cave, pouring the lava bucket and the water to set the last blocks in place. It isn't the ideal spot. "This isn't a great place to build it because it's kind of in the middle of nowhere." There's no flint, but there's gravel. "Oh, there we go, we got it right away." That makes a flint and steel.
A chest goes down beside the portal for the things that won't help in the Nether, with the plan to pick them up on the way back. The furnace comes along, because "my furnace will stop working once I go through." Then Basket steps in, and the achievement for entering the Nether shows up in chat.
Quartz and glowstone
On the other side the furnace goes down next to the portal to cook iron. There's glowstone hanging from the ceiling, and Basket breaks it down. Nether quartz is in the walls, and it gives experience. "It's not the most exciting thing, but we could make some comparators." Basket hasn't played the Nether in 1.11 before. Basket makes a few more pickaxes at a crafting table and decides how to mark the way: "I don't need to mark everything, just the turning points."
Looking for a fortress
Out in the open, Basket turns up the render distance to see farther and starts setting torches on cobblestone pillars across the netherrack. Fires are burning here and there on the ground. "We're trying to find a fortress." Lava streams cut across the path, and Basket blocks them off with cobblestone to get around. "Oh, I hear a ghast. It's not good."
There's a backup plan if this doesn't work: wait for someone else to find a fortress and head for it. "That might be what I do if this fails." Time matters, too. "I don't want to get too far from the portal because it's sort of a timed challenge."
Pigmen and a weird spot
Zombie pigmen wander the netherrack, and one walks right up. "Hi, how's it going? Go ahead." Basket bridges over another lava stream with cobblestone, backs up and tries a new direction, then digs into a wall rather than pillar up. "I'd have to be very careful about lava." Torches go down around the spot. "I should probably mark this clearly as a weird spot."
That's where the day runs out. "Actually this is the end of this episode. Will I find anything? Will I die?" The episode ends with Basket alive in the Nether, no fortress found yet, and the end card follows with no gameplay after it.