Original sentence: During the late 1980s, AD&D Second Edition was published, which revised the rules again, consolidating some character classes, disposing of some fan favorites, and revising the combat system slightly.In 1980, the Dungeons & Dragons name was used for a simplified version of the game that was incompatible with the more mainstream AD&D.In July of 2003, errata was incorporated into a new set of core rulebooks as an edition "3.5".It is the basis of a broader role-playing system designed around 20-sided dice, called the d20 system.Others are of the opinion that it needlessly complicated matters by adding tortuous rules regarding "attacks of opportunity" and putting all movement on a square grid.The d20 system is an open source version of the D&D core rules that makes it easier to market D&D-compatible content under a broadly recognizable commercial license.The edition did remove old arbitrary restrictions on class and race combinations, and incorporates skills and feats to allow players to customize their characters.This edition rationalized movement and combat, according to its proponents
Edited sentence: " It is based on a role-playing system designed around 20-sided dice, called the d20 system.During the late 1980s, AD&D Second Edition was published, which revised the rules again, consolidating the character classes, and revising the combat system somewhat.In 1980, Dungeons & Dragons was republished as a simplified version of the game.In July of 2003 errata was incorporated and a new set of core rulebooks was released as system 3.5.It rationalizes movement and combat (especially ranged combat), removes lots of arbitrary restrictions (now players can use previously forbidden classes, such as a half-orc monk), and incorporates skills and feats to allow players to customize their characters.The d20 system is an open source version of the D&D core rules that allows others to create D&D-compatible content.This version has informally been referred to by fans and players as a "third" edition of D&D, often abbreviated as "3E D&D