The following chapter of our Assassin's Creed Odyssey game guide contains a list of all Ainigmata Ostraka in the Pirate Islands. The Pirate Islands include the islands of Seriphos, Keos and Lestris. Ainigmata Ostraka on Seriphos (Blue Eyed Beauty) and Keos (Smoke Signal).
Blue Eyed Beauty on Seriphos
In Seriphos, a part of the Pirate Islands, you will find only one Ainigmata Ostraka. It is called Blue Eyed Beauty.
Location of Ainigmata Ostraka: Go to Aetios's House. You will find the item on the table inside.
Ostraka riddle solution: Go to Polydektes Lagoo and dive at the indicated spot. You will find a jug.
Smoke Signal on Keos
There is only one Ainigmata Ostraka on Keos. This one is called Smoke Signal.
The location of this Ainigmata Ostraka: Head to the Leader House. The item is on the table.
Puzzle solution: Head to the northern part of Keos. Locate an extinguished bonfire near the blacksmith. The item is in the middle of it.
A cave is located near Lestris. That cave contains one of the Ainigmata Ostraka puzzles - this one is called Pride of Place.
Pride of Place
The location of this Ainigmata Ostraka: Head to Wailing Cavern. The tablet is near the chest located at the end of the cave.
Puzzle solution: Reach the end of Keso and search for the monument depicting a lion. The solution is on the monument's back.