Medium Mob Repeller is the second tier of the Ala Industrial guard field: while the block is powered, hostile mobs flee a 16-block radius (a 33×33×33 cube) and cannot approach the base. Passive animals, villagers and calm neutral mobs stay untouched, and an angered enderman simply teleports away. The field is a constant upkeep cost — 32 EU/t charged every tick while the block is enabled, so a quiet night costs exactly as much as a siege. An internal buffer of 8,000 EU carries the field through short outages, and the zone is swept every 10 ticks (half a second), fast enough that no monster crosses it.

Medium Mob Repeller cannot be crafted: it grows out of a Small Mob Repeller when you insert a Soul Vessel filled with 80 souls, and the stored energy carries over. Filling the vessel takes roughly 4 hours of play at 15–25 personal kills per hour, because a soul is registered only when the killing blow is the player's own. As an MV consumer the block accepts up to 128 EU/t — a basic LV line tops out at 32 EU/t, so run a cable of the matching class. At 250 souls the block grows again into the Large Mob Repeller with a 24-block radius, and souls beyond the threshold burn with the vessel. A redstone signal switches the field off, while the dome button shows the zone boundary to you alone.