This set of 7 dice in Diffusion Olympus includes Arch'd4,d6, d8, d10, d%, d12, and Balance'd20. Role 4 Initiative dice average about 25% larger than traditional dice and come in a plastic display box. The Arch'd4 is a uniquely shaped die that features large top-face numbers and is easier to read, pick up, and roll. The Balance'd20 has a unique arrangement of numbers so that any 5 adjacent sides add to either 52 or 53 to ensure the most even distribution of outcomes.