Legendary monuments adds various structures / ores to the game used to spawn various Legendary Pokemon. This is closest to the base game as you need to explore for the structures and use their specific items to summon them. Can't find the structure? Craft a suitcase block and change a villagers profession to see if he will sell you a map! See the attached wiki for what items are needed to spawn what legends and more general info on the mod.
Ever struggle to find that legendary? Maybe it's deep underground but you can't tell? Well we have a wonderful tool to assist you trainer! When a legendary Pokemon spawns in, you will get a message in the chat. Click on "Add" & you will be able to generate a 3D way point that appears both on your map & in the world itself. This handy feature also applies to mythicals, shinies, and paradox Pokemon!