What Do You Do With The Tanoby Caves?
The Tanoby Ruins is a very special place. You can catch Unown there! But, in order to make Unown apear there, you must unlock them. To do this, go to Sevault Canyon on Seven Ilsand. Find the Tanoby Key there, and solve the rock puzzle with the HM Strength. Once you do, there will be a small earthquake. Now, go to the Tanoby Ruins, choose a ruin, and Unown will apear like wild Pokemon! And the best part is, you can have as many as you want!