Thudd is the first giant creature to be experimented with in Yoshi and the Mysterious Book. It is a real glutton that will try to inhale anything in sight, including Yoshi. Though it moves slowly, nothing can escape once it decides to breathe in.
Thudd’s Discoveries also heavily leans into its inhale mechanic. Yoshi will need to guide Thudd, and even be spit out, to get a lot of the discoveries to complete its creature page in Yoshi and the Mysterious Book, and we’ll show you how to get them all right here!

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Thudd’s Location in Yoshi and the Mysterious Book
You can find Thudd at the end of Chapter 2, once you have discovered every other creature in the chapter and completed their stages. There are 26 Thudd Discoveries. The text turns red when you have found all the Discoveries.
Thudd is special because there are two parts to Thudd’s Domain: Thudd sleeping at the beginning, and Thudd walking around after it is woken up.
All Thudd Discoveries in Yoshi and the Mysterious Book
All of Thudd’s Discoveries can be done within its stage, Thudd Domain.
It is possible to miss some of them, so if it looks like a Discovery is not working, just start the level over.
You can also select “End Exploration” at any time because all your Discoveries will be recorded and saved once you get them. Here’s each discovery and how to get it:
Discovery
Stage
How to Get It
Spit out a Smiley Flower
Thudd Domain
Ground Pound Thudd’s belly button while it is sleeping.
Doesn’t prefer Yoshi flavor
Thudd Domain
Get inhaled by Thudd, then spit Yoshi out.
Inhaled the Crazee Dayzee
Thudd Domain
Throw a Crazee Dayzee at its mouth.
The Thudd stood up
Thudd Domain
Carry Crazee Dayzee, then have Thudd spit Yoshi straight to the top.
Throw 5 Crazee Dayzee at the buried Heart Turnip to make it dig it up.
Roll the Heart Turnip off the edge to make Thudd swallow it and stand up.
Inhaled the entire pond
Thudd Domain
Go to the pond to the left of Thudd’s starting area.
Have Thudd inhale the water.
Inhaled a brilliant white jewel
Thudd Domain
Spit Yoshi out to break the rocks on the left of Thudd’s starting area, above the pond, to reveal white jewels.
Take a white jewel to Thudd and place it on the ground for it to inhale.
Inhaled a red teardrop jewel
Thudd Domain
Spit Yoshi out to break the rocks in the top-right of Thudd’s starting area until you uncover the red jewels.
Take a red jewel to Thudd and place it on the ground for it to inhale.
Fossil of an ancient creature
Thudd Domain
Spit Yoshi out to break the rocks in the top-right of Thudd’s starting area until you uncover a rope Yoshi can grab.
Spit Yoshi at the rope, then release to the right to uncover the fossil.
Not satisfied with apples
Thudd Domain
Go through the cave until you reach the outside area with the large pond.
Spit Yoshi at the apple trees above the pond to knock down apples.
Have Thudd inhale the apples from the ground.
Inhaled the Croakaoke
Thudd Domain
Progress through the level until you reach Bowser Jr.
Break all the stone structures until Thudd can reach and inhale a Croakaoke.
Rescued Bowser Jr.
Thudd Domain
Progress through the stage until you reach a trapped Bowser Jr.
Keep inhaling Yoshi and spitting out until all the blocks are destroyed.
Big creatures feel pain too
Thudd Domain
While Thudd is walking around, Ground Pound on its head.
To the great beyond
Thudd Domain
Have Thudd spit Yoshi out to break the rocks in the top-left portion of its starting area.
Spit Yoshi straight into the air when below the location of the Smiley Flower, high above the cave.
You can also spit Yoshi onto the rope in the top-left area, then use the momentum and aim up to reach the outside.
Spit water and revive a Smiley Flower
Thudd Domain
Have Thudd inhale water.
Go to the dry Smiley Flower at Thudd’s starting location, then spit Yoshi out to spray the water on the Smiley Flower.
Destroyed the statue
Thudd Domain
Move Thudd off the ledges to the right of its starting area.
Turn left, inhale Yoshi, and spit out in the small tunnel to the left underneath Thudd’s starting location to break the statue inside.
Spit out and cracked the nut open
Thudd Domain
Take Thudd to the area right outside the cave.
Spit Yoshi out at the rocks above to reveal and drop the nuts.
Have Thudd inhale and spit out the nuts to break them.
Inhaled the Plumebrella
Thudd Domain
Go to the large pond outside the cave.
Spit Yoshi out high into the air above the pond to find a Plumebrella.
Take the Plumebrella to Thudd, then throw it to have Thudd inhale it.
Found a Smiley Flower in the dry pond’s cave
Thudd Domain
Have Thudd inhale the large pond of water outside the cave.
Go further in to find more water and a Smiley Flower.
Have Thudd inhale the last bit of water to reach the area and the Smiley Flower.
Inhaled the Glubbit
Thudd Domain
Go to the large pond outside the cave.
To the left of the pond, there are small rocks with bubbles coming out.
Ground Pound the bubbles to reveal Glubbit, then have Thudd inhale one.
Ate the fish fossil
Thudd Domain
Spit Yoshi out to break the rocks in the top-right portion of Thudd’s starting area to reveal small fish fossils.
Take the fish fossil to Thudd and have it inhale.
Many things grow
Thudd Domain
Have Thudd inhale water, then spit out over the grassy area to the left of the large pond outside.
Inhaled the Bunchabee
Thudd Domain
After freeing Bowser Jr., go all the way to the right of the stage.
In the top-right, you’ll see beehives and some Bunchabee.
Lure the Bunchabee near Thudd, then have it inhale them.
Inhaled a Golden Springhopper
Thudd Domain
After freeing Bowser Jr., continue right until you see a boulder in the ground.
Spit Yoshi at the boulder to break it and reveal the Springhoppers
It even tried eating Kamek
Thudd Domain
Progress through the stage until you see Kamek flying around while Bowser Jr. is trapped.
Jump near Kamek to have Thudd inhale.
You must do this before saving Bowser Jr.
Every Crazee Dayzee turned into grass
Thudd Domain
Make sure Thudd does not inhale all the water in the stage.
Open the path for Thudd by breaking everything around Bowser Jr.
Once you can reach the three Crazee Dayzee, have Thudd inhale some water.
Go back to the three planted Crazee Dayzee at the end of the stage, then spit Yoshi out with the water to turn them all into grass.
Found a hidden Smiley Flower
Thudd Domain
After freeing Bowser Jr., go all the way to the right of the stage.
Spit Yoshi out in the top-right area with the beehives to reach the Smiley Flower.
Hopefully, this guide on All Thudd Discoveries in Yoshi and the Mysterious Book helped you complete some of the harder ones you might have missed. If you want to search for more collectibles, you can follow these guides:


Released
May 21, 2026
ESRB
Everyone / Mild Fantasy Violence
Developer(s)
Nintendo
Publisher(s)
Nintendo

