Join intrepid explorer Rich Wilde on an epic adventure and unravel the dark mysteries present within Tome of Madness. The game is a 5x5 grid slot where players match 4 or more symbols in clusters for wins. It features multiple Wilds and a charge Portal with various bonus features. The game is based on H.P. Lovecraft's Cthulhu Mythos and involves unlocking different features by charging the Portal with winning clusters. There's also an Other World free round with additional Portal effects and a Mega Wild Cthulhu symbol that can help create more wins.