Episode 12 of Season 2 takes the tank from Episode 11 out against the enemy bases past the wall. In between, Basket builds a train-fed smelting block into the rail grid, fixes the iron and coal lines, and ends with a tour of the oil field. When the video stops, plastic and batteries are piling up, and no train carries them anywhere yet.
Learning the tank
"It is time to expand." The tank is loaded with shells, and spare rounds go in its trunk to see whether it refills itself. The research box shows Inserter capacity bonus 3. The fight becomes a loop: shoot, back up, let the wall turrets help, go again. Every time the tank backs into the wall, the wall takes damage, and the commentary decides that is "almost worse than them hitting me."
Robots repair the tank, and Basket hops out with repair packs between runs. "It's almost like a two-person job." Down to two rockets, Basket makes one last push and backs out through trees under fire. "I think I took out that whole village... that was my first objective."
A smelting block in the grid
With the ground clear, a defended rail block goes down for the robots to build. Then a new idea: a smelting block in one of the empty squares between the rail blocks. Trains loop in and stop on either side, one to drop off ore and one to pick up plates. The design needs a lot of stack inserters, only just unlocked, so Basket goes off to make them.
After a cut, the block is done: "here is what I settled with." Ore and coal arrive on the same two-car train and stack inserters move them through rows of machines in big handfuls. It goes into a blueprint. One train keeps arriving empty, and that is left to "figure that out later." The research box now shows Worker robot cargo size 2.
A copy, and more fixes
The blueprint goes down again on another empty square, this one for copper. It sits outside the orange logistic area and inside the green one, so the robots will build it but will not bring it supplies. It needs stack inserters that are not in stock yet.
Back at the first block, iron plates come out but go nowhere. Basket renames the stations so the ore train heads there and a plate train waits "until you're not doing anything," which the commentary calls "my new thing." The old smelter's belts come out: "Now we have iron running back into the system."
Coal has stopped too. Nearby copper drills sit idle with no ore left where they mine, and the coal belt no longer loops back. Basket tears out the old belts and lays them again, which "should solve the coal problem." Then an assembler starts making stack inserters, with passive provider chests keeping a stock for the robots.
Back in the tank
The next base is close to the wall, and the robots heal the tank between runs. The trunk question gets an answer: down to two shells, "it did grab ammo from my trunk." By nightfall the area is clear. Basket picks up what the commentary calls "alien science stuff" and drops a defended straight-through block.
The oil field
Before the end comes a tour of the oil area. Pumpjacks feed oil refineries, and a chemical plant runs "Light oil cracking to petroleum gas." Four refineries sit idle because a pipe "never linked back up"; Basket adds pipe and they start. Plastic sits in passive provider chests for the robots, since there is no plastic train yet, and another line makes batteries. "We have a lot of plastic and a bunch of batteries."
Where it ends
The coal train for the oil area still is not delivering, and iron is not reaching the chests there. The plan is a train to carry plastic to a manufacturing area for red chips, which always run short, and to take the land past the wall, with coal and what the commentary believes is a huge iron deposit. Nothing is in research when the commentary calls it the end of the episode.