The three green X spots that don’t say “finish” are all minigames. When you get to one, you’ll see a bell on the ground. Interact with it to start. Bells will appear in the sky and you need to shoot them in the same order they show up.
If you mess up or forget the order, just interact with the ground bell again and it’ll show you the sequence again.
Once you get it right, don’t forget to actually pick up the bell from the ground. A lot of people miss that.
After finishing all three minigames, head to the X marked “finish” and interact with the bell at the top of the building to complete it.
The yellow X here is tied to a mission needed to unlock the Far Far North map.
The purple X marks a symbol you’ll need later for Area 41.
Desert
This one is pretty straightforward. The cactus parents marked as (b) are missing their kids marked as (a). Your job is just to bring each child back to the correct parent.
You don’t need to follow any order like 1 to 6. Just match the numbers correctly and return them.
The purple X here is again a symbol for Area 41, so make sure you remember it.
Canyon
Each green X here is its own little challenge, and each one gives you a medallion.
The northern one requires dynamite. Blow up the rocks blocking the cave and go inside. The medallion is waiting at the end.
The western one is all about shooting targets. There are 10 blue glowing targets. The first one is on the safe. If you stand on top of the rock with the safe, it makes spotting the rest much easier. Once you hit all 10, the medallion will be inside the safe.
The eastern one is a digging task. You’ll find shovels nearby. One of the dirt mounds hides the medallion. The correct mound is southeast of the X, so start there.
After collecting all three medallions, go to the X marked “finish”. You’ll find a door nearby with four slots. Place the three medallions you collected, and you’ll get the final one there.
The yellow X here is also part of the Far Far North unlock quest.
The purple X is another Area 41 symbol.
Woodland
At the green X marked “finish”, there’s a map showing mushrooms placed around the island. These mushrooms are numbered from 1 to 7.
You need to interact with them in that exact order. Once you’ve done all seven, go back to the map and interact with it again to complete the secret.
The purple X here is again for Area 41, so don’t ignore it.
Area 41
By now you should have noticed the purple X marks from Far West, Desert, Canyon, and Woodland. Each of those gives you a symbol.
Here’s what you do. Go to the green X in Area 41. You’ll need to input those symbols in the correct order. The order is shown by the dots underneath them.
Put them in correctly and that completes the quest.
The yellow X here is again tied to the Far Far North unlock.
Far Far North
The green X spots here are parts of a snowman. You don’t pick them up normally, instead you roll them by walking into them.
Guide each part to the X marked “finish” and once all parts are there, you’re done.
Jungle
Nothing extra here beyond what’s already shown, just follow the markings on the map as they are.
That’s everything covered. Just follow each step per map and you won’t miss anything.