This game is quite simple, but since I got stuck at 20 of 21 magic mushrooms for quite some time, I decided to make a map. Hope it can help you too in case you are missing something.

Needless to say, this guide is full of spoilers. I recommend you try to find everything yourself first. After the ending, you can choose "Continue" to go back to the last moment before the ending, so you can backtrack and find the stuff you missed.

To make this map usable, I divided it into a grid. Every item location will use this coordinates.

You start the game at I7, on the wanderer's house. Everything on this map is at their initial stage, except for the caves that remain hidden until you light a torch.

Runes in order of acquisition:

Location: Altar on H6/I6
Usage: Remove dead plants, revive flowers, change flower color (flower door puzzle)
Hotkey: 1

Location: Fulvous quest on F6
Usage: Breaks big rock, move column (column door puzzle)
Hotkey: 5

Location: Altar on C8
Usage: Lights torches and fireplaces
Hotkey: 3

Location: Altar on M9
Usage: Extinguishes fires, fills pits
Hotkey: 2

Location: Skiper quest on N4
Usage: Freezes a pit full of water
Hotkey: 4

Location: Elements puzzle on H9
Usage: Passes trough fallen trees (after extinguished)
Hotkey: 6

Location: Altar on E3
Usage: Dig burrows (can find items or warp to another location)
Hotkey: 8

Location: Fussy quest on F9
Usage: Crosses the abyss
Hotkey: 9

Location: Altar on J2
Usage: Scares rabbits
Hotkey: 7

Location: Felix quest on D11
Usage: Crosses the mountain
Hotkey: 0

• Acorns (Fussy quest) - Burrows on D6, G5, L8
  
• Apples (Fuffer quest) - F4, G8, M7
  
• Blueberries (Prickler quest) - C3, E9, E11
  
• Brushwood (Cheper quest) - H2, H3, H4, I1, K1, K2
  
• Fish (Stomper quest) - Cheper quest on N2
  
• Flowers (Bees quest) - E8, I5/J5, L7
  
• Honey (Fulvous quest) - Bees quest on I5
  
• Mushrooms (Wheezer quest) - E5, K5, L8
  
• Worms (Felix quest) - Burrows on L2, O9, Q7

Collecting all 21 magic mushrooms will unlock the "true ending". Almost every mushroom is easy to spot, but they also trigger an unique sound when you are close to them.

The mushrooms are listed in order, considering what runes you'll need to get them. Since the order in which you get the runes is pretty much linear, I'll only list the last rune you'll need.

After you get the Mole rune, you can use certain burrows as fast travel points. They are marked on the map with yellow icons. There are 4 warp ponts in the map:

• D2 <-> F5
  
• G7 <-> K4
  
• O7 <-> Q8 ("secret" area)
  
• E10 <-> J9