The 神秘传送门 instantly opens at the start of the 撒旦军队 event. The Mysterious Portal cannot be destroyed, and two of these will spawn 235 tiles on either side of the 埃特尼亚水晶座. They are responsible for all the enemies that spawn in the 事件, and they despawn upon the event's completion or failure. When standing in the portal while a wave is currently happening, you will continuously take damage.
- A good way to keep the enemies at bay near the Mysterious Portal is by placing an 爆炸机关 near the portal's entrance. This way the enemies will instantly take damage when they come out.