Last time the next level looked like it was at the bottom of the lake. This time they dive in and find out, then spend the back half of a short episode getting coal.
Dive, dive, dive
Scuba helmet on. One of them is expecting floating charged creepers and guardian jerkfaces. At the bottom they work out where they are: the place they just came from is called Drizzling Cove. One of them mentions a pair of gold boots with Depth Strider 3, left behind in a box.
Down here there's a guardian, and a four-way spawner with a creeper spawner on every side. The worry is that the creepers will swim up at them. They turn out to be regular creepers, not charged, and only one slowly swims up. Blocks go down to deal with the guardian, and the creeper spawners go out.
Two hearts left
The next stretch is very ocean monument-y. There's a zombie spawner to the left and another spawner on the far side. One of them kills a primed spawner, then something with gravel goes off, and he gets out of it with two hearts left. He credits his cat-like reflexes. It didn't reveal anything, as far as they can tell.
Torches are already a problem. One of them has 62. The other has eight, then seven, and no coal.
Time to be stupid
Past the pool there's a rail, then a bed, kind of. The rail runs back, and that might mean a shortcut. A sign asks: is it time to be awesome? The answer is yes. One of them doesn't trust any rail he hasn't scoped out, but they go anyway, and a second sign asks if it's time to be stupid. The answer is yes again. The drop below has no water at the bottom, just glass, and it doesn't hurt. A button sits nearby, and the way out leads back to the first level. Shortcut.
So coal
So the plan is coal. There's some right outside the base, and the Fortune pick comes out. The other host chops down some trees to make himself useful, and offers to make sticks.
While they mine they talk about what's next. They haven't touched cyan yet. The other idea is to go back to the level where they didn't get all the emeralds, because the entrance to the next level might be there, past one more hallway. Or it might just be one room. They won't know until they go.
They're getting coal. One of them is so coal. The other agrees he's pretty coal.
Buttons and signs have met their end
The rest is cleanup. They test what burns in a furnace (not buttons, but stairs do), and whatever won't burn goes into the lava. Then the stream has to end. The good news, they decide, is that they have their stuff and coal for next time. A bit of a prep work episode, but they're keeping it.