B1ackdr4g0n

You have to find the hieoglyphics laying around the islands,there are 9 this is where they are:
1st island
There is one in the deep jungle, somewhere in the middle next to a tree and just looks like a sqaure rock.
There is one in the shipwreck lagoon, it is on the massive wrecked ship
The last on the first island is on the second beach next to the ancient pier.
2nd Island.
There is one in the dark cave next to the ancient door.
There is one in skull rock jungle above the cave, to the left of the skull shaped rock.
There is one across the bridge you build in I think it's called west river plains, you can climb the chasm if you havn't built the bridge yet, it's in the middle and difficult to miss.
The last one on the second island is on the second jungle like beach with the other half of the plane in it, the hieoglyph is down by the shore on the left hand side behind a rock.
3rd island.
There is one on the hill above the hot springs, look carefully for it.
The last is in the geyser plains next to the ancient door.
If you found all 9 you will unlock the plans to make a hieoglyphic steele. Go to your workbench and build it, then go back to the door where you found the last hieoglyphic and inspect it.
Hope that helps.