Duct Unloader

The Duct Unloader is an Erekir-only transport block that removes items from the tile directly behind it and outputs them in the direction it faces. It functions as a directional, in-line transfer device rather than a storage or processing building: it does not store items itself and performs only immediate unloading and forwarding of resources. The block is commonly used to extract items from Reinforced Container, Reinforced Vault, Container, or other buildings placed behind it and push those items onward without local buffering.

The Duct Unloader reads items from the block on its rear side (the tile opposite the direction it faces) and emits items out of its front side (the direction it faces). When a specific filter is set, the Duct Unloader will only output the selected item type; if no filter is set, it will choose items from the source block at random. Unlike Serpulo’s Unloader, the Duct Unloader cannot take items from a core; it only interacts with non-core buildings behind it.

Because the Duct Unloader has no internal item capacity, it never accumulates inventory. This design means an unconfigured Duct Unloader that sends directly to a destination building will not become clogged by incorrect items: any item it receives is immediately attempted to be passed on. This makes it suitable for single-file extraction where buffering is undesirable or could cause jams. The block consumes no power or items to operate.

Practical usage and interactions:

• Place the Duct Unloader with its front facing the intended destination and its rear adjacent to the source building. It extracts only from that rear tile.
• Use the filter to enforce deterministic unloading of a single resource; leave the filter off if unloading mixed or random items is acceptable.
• Because it has no capacity, do not place additional transporters between a Duct Unloader and its destination if you rely on the no-clog behavior — intermediate inventories can cause jams from unwanted item types.
• The Duct Unloader can be controlled by logic to change its filter and thus the type of item it unloads (allowing dynamic routing based on scripts or signals).
• The block is grouped with transport blocks in the game’s classification, in contrast to Serpulo’s Unloader which is categorized with effects, core, and storage blocks; this reflects the Duct Unloader’s focus on item routing rather than storage or core interaction.

Design notes:

• The Duct Unloader is intended for precise, directionally constrained transfers and fits designs where immediate forwarding is preferable to local buffering.
• Avoid using it to extract from cores; it does not support core unloading.