Book of Endless Life
Finding the Book of Endless Life doesn't get the party very far—it needs to be opened, a task that is not so simple as undoing a clasp. To access this powerful enchanted tome the adventurers must seek out an expert on the Library of Wholeness (such as the sage Loremaster Dalwyn), find runestones to help finish crafting the ivy key needed to unlock the book, best the dwarven spirits roaming Karridan-Bakkal (alongside monsters aplenty), and hunt down a fell leech for the components to complete the opening ritual. Within the dungeon there waits another enemy however, a necromancer with a corrupted Tome of Decay eager to take their treasure for himself!
My latest adventure for the En5ider Patreon, is one I particularly enjoyed creating. A subscription to the patreon gets you access not just to this but to another 463 - and counting - 5th Edition articles, from full adventures, to new spells, new magic items, and new monsters.