If you're asking about the plain old **Mushroom Spores**, the spores you get from any plain mushroom, then I'm convinced that they serve no other purpose in the game and only have a one time use.

>! Healing **Orielle's**  **Loftwing**

I've done a fair amount of testing and could not find a single use for them.  Everything I've tried it on does absolutely nothing:

* Hearts (On flowers or on their own)
* Rupees (Green, Blue, and Red)
* Ammo (Seeds)
* Catchables (Grasshoppers, Hornets, Rhino Beetles, Non-Blue Birds)
* Enemies (ChuChus, Bokoblins, Octorocks, Guays, Keese)
* Friendly Characters (Kikwis, The old lady)
* Diggable holes

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If on the other hand you are asking about the **Glittering Spores**, the spores you get from the glittering mushrooms, they have very limited uses AFAIK.  There's only a couple of uses that I know of.

You can use it on **Hearts** or **Rupees** to change them.  **Hearts** turn into **Fairies**.  **Rupees** turn into different valued rupees, even a **Rupoor**.

On some of the smaller enemies, it knocks them dizzy.  I was only able to do this on **Bokoblins**, **Octorocks** and **Babas** (the plants) but didn't have enough to test on others.