Four Against Darkness is a solitaire dungeon-delving game.
No miniatures are needed. All you need is the book, a pencil, two six sided dice, and grid paper.
You choose four character types from the classic classes (warrior, wizard, rogue, halfling, dwarf, barbarian, cleric, elf), equip them, and start adventuring in dungeons created by dice rolls and by your choices. When you enter a room, you generate its content on a series of random tables. You will meet monsters, fight them, hopefully defeat them (or decide that discretion is the better part of valor!), you'll manage your resources (healing, spells, life points, equipment), grab treasure, dodge traps, find clues, and even accept quests from the monsters you meet. Your characters can level up and become better at what they do, but it will not be easy.