NPC Spawner (Thin Plate)

The NPC Spawner (Thin Plate) is a spawner that's appearance can be changed with the Texture Tool to appear exactly like the blocks in its surroundings to disguise it. It is a variant of the Alien Blocks that is in some hostile POI's and Trade Stations alike. A good indicator that an NPC Spawner (Thin Plate) is hidden in the room of a POI, is if you observe Fauna spawning in there whenever you enter that room and the respawn conditions are met, but no other spawner is visible. It should be noted that while the NPC Spawner (Thin Plate) and the NPC Spawner (Pad) do not have a power requirement listed, they do in fact require 1.00 kW of power as well as an Alien Core to function.

Behaviour & Characteristics
The NPC Spawner (Thin Plate) and the NPC Spawner (Pad) both work the same and their color can be changed with the Color Tool. The only difference between the two is appearance and that the texture of the NPC Spawner (Thin Plate) can be changed with the Texture & Symbol Tool, while the texture of the NPC Spawner (Pad) cannot be changed. They are similar to a Motion Sensor, in that when a player enters the boundaries the spawner is set to detect players in, it will activate. It can then spawn a certain number of Fauna depending on its settings. If a Fauna has been killed, after its corpse despawns in two minutes, the spawner will be able to spawn another Fauna in its place if the player is in the spawner boundaries.

Spawner Settings
In Creative Mode, the spawner's range of detection can be customized to up to 16 blocks in 5 directions when the spawner is counted as the 1st block in any direction. The number of Fauna that will spawn can be customized to any number between 0 and 999 and can be set to include up to 4 different types of Fauna that have a chance of spawning. This means that the different types of Fauna you select to be able to spawn will not necessarily spawn in an equal ratio to each other.

Finding a Disguised NPC Spawner (Thin Plate) in POI's in Survival Mode
Even though an NPC Spawner (Thin Plate) might be disguised as a normal block, you can still find them if you wish in Survival Mode if one is present in any POI, whether it is a hostile POI or a Trade Station. To do this, you will need a Multitool. First, observe the spot you see the Fauna spawning from. Second, equip your Multitool and point it at the blocks in the vicinity of where you saw the Fauna spawning in from. You will know you've found an NPC Spawner (Thin Plate) when your Multitool's HUD says "NPC Spawner (Thin Plate)" as the block name when you are pointing your Multitool at what might look like a normal block.

(Player finding an NPC Spawner (Thin Plate) in a POI using a Multitool)