In this occult sacrificial temple or altar room, the tortured souls of previously tortured and sacrificed prisoners emerge again from the depths of hellish lava to exact vengeance.
This sacrificial temple is intended for decorative/atmospheric purposes and can be connected to a spawner mob farm (skeletons or zombies) as a little extra. I deliberately designed the room with cool stone steps, polished andesite and strong dark colors (obsidian, nether bricks, charcoal blocks) to create a gloomy mood.
The mobs (here skeletons) are brought by a stream of water to central under the lava basin. There they gather until the player activates the "Ghost Summoning", then the mobs rise, emerge from the lava and come, depending on the armor then quickly perish.
I came up with this idea in the context of a skeleton farm I built as a dilapidated prison camp ruin. Besides the actual XP and bone farm, I added a quarry, cells, watchtowers and this very sacrifice room to create a fitting, atmospheric setting for the farm:
Instructions:I'm not going to go into further detail about the "standard transport" of mobs by water stream away from a spawner.
If the mobs then get under the lava field via water flow, they gather there until the player activates the ascent and the mobs emerge one after the other. To do this, a launcher is activated via a redstone signal (here: lithographic plate),
which contains a water bucket, so that it is emptied and a small simple water mob elevator(sign, water, sign) is created.
In the center of the lava field is the hole where the mobs then rise, the upper shield prevents the lava from flowing down,
so that the mobs emerge through the lava and thus burn in it.