In Stranger Things 2, they say the portal takes a lot of energy to close, and that only El has the power to close it. But in the first season, portals to the Upside-Down crop up all over the place- in the Byers' home, in the tree in the woods, and by the swimming pool. What's the difference between the Hawkins' lab portal and the other ones?
1 Answer
The wiki states that the smaller portals were inter-dimensional "wounds" that would close/collapse quickly after forming, and that only the Demogorgon could make them because they took a lot of energy to create. Presumably the "demo dogs" are too weak to make portals like this, which is why they dig the tunnels instead.