A mob maker. The circle does nothing until you bind it by right-clicking it with an item. An item a mob drops binds it to that mob (if several mobs drop it, any of them may appear). Wheat seeds stand for peaceful animals, nether wart for Nether mobs, and a bone block for the Overworld's undead. After that it spawns on its own, ignoring light, biome and ground. It will not spawn monsters on Peaceful.
Higher levels do not change what appears, only how fast: the circle banks health points every second and spends them on mobs, so a tougher mob takes longer to build up. The biggest mobs also make the circle wait until the last one is gone before it starts again. The circle covers a single block at every level.
| Circle | Mana (cast) | Mana upkeep (per batch) | Mana working (per batch) | Spawn HP (per batch) |
|---|---|---|---|---|
| Spawn I | 200 | 1 | 12 | 4 |
| Spawn II | 200 | 1 | 12 | 9 |
| Spawn III | 200 | 1 | 12 | 14 |
| Spawn IV | 200 | 1 | 12 | 19 |
| Spawn V | 200 | 1 | 12 | 24 |
| Spawn VI | 200 | 1 | 12 | 29 |
| Spawn VII | 200 | 1 | 12 | 34 |
| Spawn VIII | 200 | 1 | 12 | 39 |
| Spawn IX | 200 | 1 | 12 | 44 |