As there are 120 floors in the mine and 112 days in the stardew year you should be able to say.
Stardew valley mushroom floors and infested levels.
They can be grown from wild seeds fa or in mushroom bins in the the cave if the mushroom option is chosen.
It does not show in 0 s or 5 s floors.
It does not yield seeds when shaken or chopped down but it will spread seeds like a common tree.
The purple mushroom is found via foraging in the mines starting at level 81 the skull cavern from a tapped mushroom tree rarely or grown in the mushroom cave rarely.
Infested floors use the same rules as mushroom levels in that they travle a floor up the mine each day.
It can be chopped down using an axe and will drop 5 6 red or purple mushrooms plus one for the stem.
They can also be found in the secret woods during spring and fall and on the forest farm during summer.
You could return to the same level multiple times per day and it would always be infested and would move one level up in the mine each day you rested.
One reason you are not finding the mushroom floor is because the mushroom floor has a chance to spawn zero mushrooms.
Each passing day the floor moves backwards.
On year 2 summer 8th the infested level was at 53 on year 2 summer 12th the infested level was at 49 the pattern continued consistently on the.
They can also be obtained by tapping a mushroom tree.
So far i have tested this over a 5 day period when i found the infested floor on floor 68.
I noticed today while playing the a level infested with slimes was moving in a predictable pattern.
This makes them farm able which is important for those looking to get two rings in particular.
If its floor 117 today it will be floor 116 the next day.
However the mushroom floor will not appear on floors ending in a 5 or a 0.
Meaning one day it can be floor 90 and you won t see it.
A mushroom tree is a tree that spawns according to a rare event in fall.
If unobstructed seeds spread by a mushroom tree have a 20 chance to grow to the next stage each day during spring.
Mushroom floor is in 80 120.
The common mushroom is a mushroom found via foraging throughout stardew valley in the fall.
So the wiki says.
An infested floor will always be on the same level for each day and goes up one level the next day assuming that everyone starts with the same level infested can someone verify you should be able to chart out what floors are infested when.
However it does not move to the next floor that floor still counts as a day so there will be no mushroom floor on the days it lands on a 5 or a 0.
Purple mushrooms can also be found on the forest farm map during the fall.
