This input into gpt-4-turbo always returns incomplete and short answer

I am accessing GPT-4-Turbo via Lmsys and slide the optput size slider to the max.

This is the prompt:

The plot is as follows: in 1986, after the Chernobyl disaster, the KGB staged a coup against Gorbachev and deposed him. This lead to a civil war in the USSR with some external actors involved.

In this fictional universe, many things which are hype in our timeline, turned out real: there exists red mercury, torsion fields and other similar things from the era, and in fact are the secret technologies developed in the USSR. The army uses torsion field generators, for instance.

There is also a Buran orbiter in space that interacts with the events.

(and regarding the atmosphere, yes, all the army uses the iconic STSh-81 “Sfera” helmets)

The output is always a few sentences and breaks in the middle of a phrase.