A
regular icosahedron that probably every
tabletop role-player has seen, this
die is perhaps the most
famous of the
polyhedral dice. Each of the little
triangular faces has a number from 1 to 20 on it. Though it lacks the strange
shape of the
d10 or the strange
rolling method of the
d4, the sheer
number of
sides can be
intimidating to a complete
gaming newbie.
In all the incarnations of D&D and AD&D, this die is used for core rolls such as attack rolls, saving throws, and ability checks. In 3rd Edition D&D, the d20's role is vastly expanded, making it the most important die by far in the new version of the game.