Heart of Ice (Virtual Reality Adventure #5) by daelsepara

Legend says that the one who possesses the Heart of Volent shall wield ultimate power. Created in the searing fires of the Big Bang, this fabulous gemstone focuses the cosmic forces which shape the universe itself. As cahos grows and a new Ice Age closes its grip on the world, you and handful of desperate adventurers compete in your search for the gem. Are you ruthless and resourceful enough to win its power for yourself?

An unofficial adaptation of the 1994 Virtual Reality Adventures book by Dave Morris.