Thudd is the first giant creature to be experimented on Yoshi and the mysterious book. He is a true eater who will try to inhale anything in sight, including Yoshi. Even if it moves slowly, nothing can escape once it decides to inhale.
Thudd's Discoveries also relies heavily on its breath mechanism. Yoshi will have to guide Thudd and even spit him out to get lots of discoveries to complete his creature side in Yoshi and the mysterious bookand we'll show you how to get them all here!

How long is Yoshi and the Mysterious Book?
Here's how long it will take you to beat Yoshi and the Book of Secrets main story and reach 100% completion.
Thudd's location in Yoshi and the Secret Book
Thudd can be found at the end of Chapter 2once you've discovered all the other creatures in the chapter and completed their stages. There are 26 Thudd Discoveries. Once you find all the discoveries, the text will turn red.
Thudd is special because Thudd's domain has two parts: Thudd sleeps at the start and Thudd walks after awakening.
All of Thudd's discoveries in Yoshi and the Secret Book
- All of Thudd's discoveries can be made within his phase, the Thudd domain.
It is possible to miss some of them, so if Discovery doesn't seem to work, start the level again.
You can also select “End Exploration” at any time, as all your discoveries will be recorded and saved as soon as you earn them. Here is each discovery and how to get it:
|
Discovery |
Phase |
How to get it |
|---|---|---|
|
Spit out the smiley face flower |
Thudd domain |
Ground Pound Thudd's navel while he sleeps. |
|
He doesn't prefer the Yoshi flavor |
Thudd domain |
Get inhaled by Thudd and then spit out Yoshi. |
|
Crazee Dayzee inhaled |
Thudd domain |
Throw a Crazee Dayzee into his mouth. |
|
Thudd stood up |
Thudd domain |
Carry Crazee Dayzee, then have Thudd spit Yoshi right on top. Throw 5 Crazee Dayzee at the buried turnip heart to dig it up. Roll the Heart Turnip off the edge for Thudd to swallow and stand up. |
|
He inhaled the entire pond |
Thudd domain |
Go to the pond to the left of the Thudda starting area. Let Thudd inhale the water. |
|
He breathed in the brilliant white gem |
Thudd domain |
Spit out Yoshi to break the rocks to the left of Thudd's starting area above the pond to reveal white gems. Take Thudd's white gem and place him on the ground so he can breathe. |
|
He breathed in the gem of red tears |
Thudd domain |
Spit out Yoshi to break the rocks in the upper right of Thudd's starting area until you reveal red gems. Take Thudd's red gem and place him on the ground so he can breathe. |
|
Fossil of an ancient creature |
Thudd domain |
Spit Yoshi to break the rocks in the upper right corner of Thudd's starting area until you reveal a rope for Yoshi to grab. Spit Yoshi onto the rope, then drop to the right to reveal a fossil. |
|
Dissatisfied with apples |
Thudd domain |
Go through the cave until you reach an outer area with a large pond. Spit Yoshi on the apple tree above the pond to knock down the apples. Let Thudd inhale apples from the ground. |
|
Croakaoke breathed |
Thudd domain |
Continue through the level until you reach Bowser Jr. Smash all the stone structures until Thudd reaches and inhales the Croakaoke. |
|
Saved by Bowser Jr. |
Thudd domain |
Go through the stage until you get to the trapped Bowser Jr. Keep inhaling Yoshi and spitting until all the blocks are destroyed. |
|
Large creatures also feel pain |
Thudd domain |
As Thudd walks around, Ground Pound to the head. |
|
On to the big ones |
Thudd domain |
Have Thudd spit Yoshi to break the rocks in the upper left of his starting area. Spit Yoshi right into the air when he is below the Smiley Flower location, high above the cave. You can also spit Yoshi onto the rope in the upper left, then use momentum and aim up to reach the outside. |
|
Spit water to revive the Smiley Flower |
Thudd domain |
Have Thudd inhale the water. Go to the dry Smiley Flower at Thudd's starting point, then spit Yoshi to spray water on the Smiley Flower. |
|
He destroyed the statue |
Thudd domain |
Move Thudd off the ledge to the right of his starting area. Turn left, inhale Yoshi and spit in the small tunnel to the left under Thudd's starting point to break the statue inside. |
|
He spat and cracked open the nut |
Thudd domain |
Take Thudd to the area right outside the cave. Spit Yoshi on the rocks above to reveal and drop the nuts. Have Thudd inhale and spit out the nuts to crack them. |
|
He breathed in Plumebrella |
Thudd domain |
Go to the large pond in front of the cave. Spit Yoshi high into the air above the pond to find a Plumebrella. Take the Plumebrella to Thudd and then throw it so that Thudd inhales it. |
|
I found a smiley face in the dry pond cave |
Thudd domain |
Have Thudd breathe in the large pool of water in front of the cave. Go further to find more water and a Smiley Flower. Have Thudd inhale the last bit of water to reach the area and the Smiley Flower. |
|
Glubbit breathed |
Thudd domain |
Go to the large pond in front of the cave. To the left of the pond are small stones with protruding bubbles. Ground Pop the bubbles to reveal a Glubbit, then have Thudd inhale one. |
|
He ate a fish fossil |
Thudd domain |
Spit out Yoshi to break the rocks in the upper right of Thudd's starting area to reveal small fish fossils. Take the fish fossil to Thudd and have him inhale it. |
|
Many things grow |
Thudd domain |
Have Thudd inhale the water and then spit it out across the grassy area to the left of the large outdoor pond. |
|
Bunchabee breathed |
Thudd domain |
After freeing Bowser Jr. go to the far right of the stage. In the upper right you will see beehives and some Bunchabees. Lure a Bunchabee near Thudd and then have them inhale. |
|
Golden Springhopper inhaled |
Thudd domain |
After freeing Bowser Jr. keep going right until you see a boulder in the ground. Spit Yoshi on the boulder to break it open to reveal Springhoppers |
|
It even tried to eat Kamka |
Thudd domain |
Go through the stage until you see Kamko flying around while Bowser Jr. he is imprisoned. Jump near Kamk to make Thudd breathe. You must do this before saving Bowser Jr. |
|
Every Crazee Dayzee turned into grass |
Thudd domain |
Make sure Thudd doesn't inhale all the water in the phase. Clear the way for Thudd by smashing everything around Bowser Jr. Once you get to three Crazee Dayzees, ask Thudd to inhale some water. Return to the three planted Crazee Dayzees at the end of the stagethen spit Yoshi with the water to turn them all into grass. |
|
He found the hidden Smiley Flower |
Thudd domain |
After freeing Bowser Jr. go to the far right of the stage. Spit out Yoshi in the upper right beehive area to reach the Smiley Flower. |
Hopefully this guide to All Thudd discoveries in Yoshi and the mysterious book helped you complete some of the harder ones that you may have missed. If you want to search for more collectibles, you can follow these instructions:

- Released
-
May 21, 2026
- ESRB
-
All / Mild fantasy violence
- Developers
-
Nintendo
- Publishers
-
Nintendo