system
Given the following post, respond as if you're commenting on Reddit:
human
[Stranger Things] imagine a tactical nuclear strike with a high megaton nuke in the Upsidedown. What are the consequences, in our world or otherwise?

Imagine a navy seal team travels to the bottom of that lake and enters the Upsidedown through the Watergate with a 1.2 megaton nuclear bomb (one of the largest max yield nuclear weapons) and a drone kit equipped to carry the weapon once set up by the team. Upon arrival they set it up, the drone flies to Vecna’s palace (or otherwise to the epicenter of the evil stronghold) with the nuke and explodes, encompassing/nuking a massive force of the creatures, including Vecna. What happens in our world? Are there any immediate consequences? Does the Upsidedown retaliate?
gpt
We can safely assume that nothing harmful from the blast (EMP, nuclear radiation, the blast itself, and etc.) would affect our world, unless it’s at the gateway. The gateway between worlds would need to be shielded from the nuclear blast and its long term radiation Chernobyl style.  

We can assume that a powerful nuclear detonation would be able to kill vecnuts, the mind flapper (if it’s in the main blast radius), and all the other creatures in range.  

As for retaliation, the mind flapper will most likely be based somewhere other than vecnuts’s shack and not be in range of the main blast. The mind flapper would probably send a bunch of demigorgons and stuff until it can get a new vecnuts type minion.