Sorry if someone already asked this.

Let's say that when you enter a specific room, there's 50% of nothing happening or 50% of you getting an event (from a pool of, say, 10 events.) How would one do that? And is it possible to change the percentages of events? Say, so that is less likely you get the same event twice in a row? (As well as adding new events/removing certain events).

At least one of these should have the answer:

https://textadventures.co.uk/forum/quest/topic/5whcwzrh_e2vwiwjmxpkvg/random-objects-encounters-in-different-areas-of-the-game
https://textadventures.co.uk/forum/quest/topic/6vtxgb5shkuv3z7gl2my-w/question-about-random-chances
https://textadventures.co.uk/forum/quest/topic/ew8cs3na3u2-ccce-nbabq/using-random-chance-for-multiple-event-combinations