Up until recently I have been going to a hole in the ground in my Aroma's Mining World to kill Wither bosses manually. It had been fine as I have not needed many Nether Stars. But it was getting a bit tiresome and saw it as a chance to make another practical build
I am building this mostly just for fun and as a cool little feature. It is not efficient or fast. I am also building it with mobGriefing set to false, so the wither is easily contained and will not break anything.
Welcome to the "maximum security dungeons execution chamber"
Down below in what is RPed as the dungeon, we find the usual wither spawning mechanisms:
I built it quite compact to hard to get a good shot
A row of Autonomouse Activators placing Soulsand and another row placing Wither Skulls on redstone signal.
Also a single Endoflame(out of shot) producing Mana.
Inside:
(Removed the wall for this shot)
Once the Wither spawns, it is pulled by a Corporeal Attractor onto the Drawbridges which then extends(and turns off the Attractor), bringing the Wither up into the cage above.
Killing the Wither:
(This and the next picture is taken holding a Botania wand)
Around the cage I have placed 3 Redstone Mana Spreaders with "Bouncing Damaging" lenses. These are set to shoot through openings in the walls of the cage(plugged with Abstruse Platforms camouflaged with the glass) and aimed to bounce around inside the cage. The angle ensures that the burst doesn't just bounce straight back out again.
Different angle:
I decided to have the Spreaders charged by other spreaders, despite the slight loss. This was due to how I could avoid having Mana Pools at the Redstone Mana Spreaders and therefore build them up like small "turrets" of some sort(They use so little Mana that it is hilarious. I could probably have charged the main Mana pool once with a tablet and forgotten all about it
).
Time to introduce a Wither:
It turns out that the Bouncing Damaging bursts hurt each bounce that pass the boss. And they also seem to bounce off the boss in rather unpredictable ways, resulting in lots of accumulated hits per burst
Even if the Wither moves off to one side, its hitbox seems to be large enough for the bouncing bursts to hurt it(even though it looks like it is bouncing back and forth besides it).
The Damaging bursts does not count like a player killing the wither, so no special drops will drop. But that just means that no Sigils will drop, which is a Win in my book
You still get Nether Stars and Yellow Hearts.
The drops are picked up by a Random Things "Advanced Item Collector" attached to a ME interface hidden under the bridge.
Oh and if anyone was wondering:
3xState Cell, 2xTimer and 2x Not gate.
One State Cell's(top middle of the picture) constant output triggers the Drawbridges. This signal is inverted with a Not gate(Top left) to the Corporeal Attractor. The release of the constant signal will start a Timer which pulse restarts the State Cell(restart the cycle).
The previous Timer pulse also triggers another State Cell(far right) which end pulse triggers the Autonomous Activators placing the Wither Skulls. Using a separate State cell here to get the timing right.
The timer pulse also triggers the Third State Cell(Bottom left) which constant output is wired into a NOT gate. This NOT gate then releases a Timer, which pulses the Redstone Mana Spreaders.
By adjusting the timings on the State Cells and Timers it is then possible to have it: Spawn, lower drawbridges, pull Wither, rise drawbridges, start firing, spawn, (wither dies), stop shooting, lower drawbridges, pull Wither, rise drawbridges, start firing...
To stop the system, apply a redstone signal to the first two State Cells on the Lock side(make sure it is after it have brought up a wither and before it has spawned a new, or a Wither will be stuck down in the spawning area).
