What seems to be the most unknown upgrade in the game, I happened to stumble upon accidentally. It's located in the second area of the game, a.k.a., the first cave you visit. You should collect as many hallucination mushrooms as you can, until you reach the rock bridge guarded by two flying enemies:

Once here, look at your left nearing the next room, and take two hallucination items. Once shroom will make a platform visible, while the other will make the wall near it disappear:

This is a maze. I don't know the exact route. All I can say for sure is:

• Your time is limited: Make sure you don't run out of the level two hallucination state, otherwise you'll be kicked out of the maze.
  
• Take the first turn to the right: Honestly, that's all I could remember before stumbling upon dead ends. You'll know if you're about to reach it because you'll have to jump off a small cliff, and you'll see your target in the distance.
  
• Save: Right after the stone bridge, there's a checkpoint. Take advantage of it. If you fail, reload. If you need more shrooms, drop off the bridge to get more (there are like, three down there).

You will meet The Wizard, who hopes to see you at some other point in the future... but who will grant you a health upgrade:

I'm not sure if the health upgrade depends on anything, but while I expected it to raise my health by one, it did by three, making my total health 8.

While the health upgrade is unlocked very early into the game, this one... is near the end of the adventure, in the purple area:

Once again, we're interested in reaching a bridge. This time, the one that leads to The Temple The Robot Factory:

Once at the bottom there will be an onslaught of enemies.

Once defeated, go back up through the area where the big triceratops-like enemies came from, and you'll stumble upon a hut:

Once there, we'll meet a Hermit, who after answering our questions will hand us the RDB.

The exit is to the right :)

I am aware this is a bit of a micro guide, but considering I was able to find all the upgrades, that some people are struggling to find them, and that this game has no guides (at the date of making this one); I took it upon myself to guide this game a bit more love.

Please let me know if you find any kind of typos or mistakes!

♡ ∩_∩
｡ („• ֊ •„)♡
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