You can interact with the mailbox in Dream-state Vanarana to get the 14th and 15th paintings. Remember that you can only get 1 painting per day so if you didn’t get these two before, you need to wait for the daily reset before you can get the last one~ There is no achievement here.
Mysterious Clipboard 14
➥ Do you remember when you got Liloupar for the first time? Yeah, the chest is near that place. Teleport to a waypoint in Safhe Shatranj. follow the Four Leaf Sigils to the underground area through a triangle gate door (There’s a Primal Construct in front of it) and enter the gate that will lead further underground on the northwest. Go to the giant tree near the debris and the bush, the Dig option can be seen near the root of the tree.
Mysterious Clipboard 15
➥ Teleport to the waypoint near Setekh Wenut and jump into the hole. Head southeast (there will be a Seelie in that direction) and follow it until you found a secret path that leads further underground.
➥ At the Wenut Tunnel, there will be a Blessbone Scorpion, go to the Remarkable Chest at the north and follow the path until you see another hole to the right of a Dendro totem. Enter that hole to reach the spot on the painting.
➥ The Dig option is near the Crystal Chunk and Mint Flower.