Most reviewers praised the mission design of the single-player campaign for positively deviating from the standard real-time strategy game formula.

Warcraft III: The Frozen Throne is a real-time strategy video game that puts players in control of a group of units and buildings in order to achieve a variety of goals.

[1] The food limit and the upkeep requirements, which dealt a penalty on resource gain when too many units were active at the same time, have both been increased slightly, leading to the ability to mobilize somewhat larger and more powerful forces.

[2] In addition to treasure items found in the main game, enemies now will also leave "runes" upon defeat that can be used to replenish health or mana.

[2] According to level designer Tim Campbell, the company failed to come up with a plausible story-based reason why orcs should appear in the main story line.

[12] Blizzard instead decided to create a more RPG-driven campaign that focuses on controlling one or multiple heroes on a network of interlinked maps.

[12] As such, base building, resource gathering and unit training are absent from most of the campaign while heroes can be leveled up past the normal 10-level limit.

[10] The expansion includes 62 new multiplayer maps and custom scenarios based on popular mods and allows up to twelve players at the same time.

[5] The Frozen Throne also includes an improved version of the World Editor program that can be used to create custom maps and scenarios to play against the computer or other players.

[16] In the main game, the human paladin Arthas Menethil was corrupted by the Lich King Ner'zhul, an undead sorcerer entrapped in ice (the titular "Frozen Throne"), and became his lieutenant.

In the events leading up to the victory against the Legion, Night Elf leader Tyrande Whisperwind freed the imprisoned Illidan Stormrage.

When Tyrande is swept away by a river while helping a group of Blood Elves led by the prince Kael'thas, Maiev convinces Malfurion that she died to maintain their pursuit of Illidan.

Arthas returns to the Undead-controlled regions of Lordaeron where three dreadlords loyal to the Burning Legion - Balnazzar, Detheroc, and Varimathras - rule.

While purging the kingdom of the remnants of the Alliance aided by Sylvanas Windrunner and the Lich Kel'Thuzad, Arthas notices that his powers have diminished.

The Lich King telepathically contacts Arthas and explains his loss of power is a result of Illidan's attacks, and summons him to defend the Frozen Throne.

With the help of Varimathras, she kills the remaining two dreadlords and Garithos and declares Lordaeron the home of the free undead, rechristened the "Forsaken".

Untouched by the events in Lordaeron and Northrend, Horde Warchief Thrall builds a new kingdom called Durotar on the continent of Kalimdor.

[18] With the previous success of StarCraft: Brood War, expectations were high for Blizzard to create another expansion that rivaled the original in both length and new content.

[21] On April 1, 2003, Blizzard teased that the Pandaren would become a fifth faction in the upcoming expansion and even created an entry on the official homepage detailing heroes, history and units.

[22] While this was only an elaborate April Fools' Day prank, the final expansion did include the Pandaren Brewmaster as one of the neutral heroes which could also be unlocked in single-player in a secret mission.

[36] Conversely, PC Gamer considered the cutscenes using the in-game graphics dated and called the voice-acting "a tad amateurish".

[2] Despite the praise, reviews also noted that the expansion's story is more buildup than resolution when it is supposed to be the culmination of the main game's storyline.

[1] Many reviewers also liked the choice to have a separate Orc campaign with its RPG elements, likening the gameplay to Blizzard's Diablo series.

[9] Strategy Gaming Online opined that the multiplayer "felt like a letdown" as it lacks some of the features of the campaign but admitted that the improvements made were significant and enhanced the experience.

[45] The editors of Computer Gaming World nominated The Frozen Throne for their 2003 "Expansion Pack of the Year" award, but it lost to Battlefield 1942: Secret Weapons of WWII.

[46] It was also a runner-up for Computer Games Magazine's "Expansion of the Year" award, which ultimately went to EverQuest: Lost Dungeons of Norrath.

[47] The Age called The Frozen Throne the best expansion pack for PC of 2003,[48] while GameSpot named it the best computer game of July 2003.