The 4th edition of the Dungeons & Dragons tabletop roleplaying game overhauled the game's systems. Changes in spells and other per-encounter resourcing give all classes a similar number of at-will, per-encounter and per-day powers. Powers have a range of effects including inflicting status effects, creating zones, and forced movement, making combat very tactical for all classes but essentially requiring use of miniatures, reinforced by the use of squares to express distances. (wikipedia.org)