The fourth main installment of the Final Fantasy series, the game's story follows Cecil, a dark knight, as he tries to prevent the sorcerer Golbez from seizing powerful crystals and destroying the world.

A sequel, Final Fantasy IV: The After Years, was released for Japanese mobile phones in 2008, and worldwide via the Wii Shop Channel on June 1, 2009.

[16] Final Fantasy IV introduced Square's Active Time Battle (ATB) system, which differed from the turn-based designs of previous RPGs.

The game employs the Super NES' Mode 7 technology to give enhanced magic spell visuals and to make airship travel more dramatic by scaling and tilting the ground for a bird's eye view.

The Lunarians are a race of beings originally from a world which was destroyed, becoming the asteroid belt surrounding the Blue Planet, and are identified by a moon-shape crest on their foreheads.

The main character, Cecil Harvey, is a dark knight and the captain of the Red Wings, an elite air force unit of the kingdom of Baron.

[17] During his quest, Cecil is joined by others, including Rydia, a young summoner from the village of Mist; Tellah, a legendary sage; Edward Chris von Muir, the prince of Damcyan who is a bard as well as the husband of Tellah's daughter Anna; Yang Fang Leiden, the head of the monks of Fabul; Palom and Porom, a black mage and a white mage, twin apprentices from the magical village of Mysidia; Edward "Edge" Geraldine, the ninja prince of Eblan; and Fusoya, the guardian of the Lunarians during their long sleep.

He uses Golbez to do this by controlling him and Kain with his psychic powers to activate the Giant of Babil, a huge machine created to carry out the genocide and take over the world.

On the airship, Kain appears and demands Cecil retrieve the final crystal in exchange for Rosa's life,[32] which the party obtains with assistance from a bedridden Edward.

After escaping a trap set by Golbez, the party flees the underworld aboard the Enterprise, with Cid sacrificing himself to reseal the passage between the two worlds and to prevent the Red Wings from continuing their pursuit.

During the epilogue, most of the cast reunites to celebrate Cecil and Rosa's wedding and their coronation as Baron's new king and queen, while Kain is seen atop Mount Ordeals, having vowed to atone for his misdeeds.

[46] According to Tanaka, he originally wanted the title to have a "more action-based, dynamic overworld" but it "wound up not being" Final Fantasy IV anymore, instead becoming a separate project that eventually became Seiken Densetsu 2 (Secret of Mana), which was codenamed "Chrono Trigger" during development.

[2][49] The Active Time Battle (ATB) system was conceived and designed by Hiroyuki Ito when he was inspired while watching a Formula One race and seeing racers pass each other at different speeds.

[54] The themes of the game were to go "from darkness to light" with Cecil, a focus on family and friendship among the large and diverse cast, and the idea that "brute strength alone isn't power".

[49] Tokita feels that Final Fantasy IV is the first game in the series to really pick up on drama,[48] and the first Japanese RPG to feature deep characters and plot.

[55] The game's script had to be reduced to one fourth of its original length due to cartridge storage limits, but Tokita made sure only "unnecessary dialogue" was cut, rather than actual story elements.

Uematsu has noted that the process of composing was excruciating, involving trial and error and requiring the sound staff to spend several nights in sleeping bags at Square's headquarters.

The English localization of Final Fantasy IV retains the storyline, graphics, and sound of the original, but the developers significantly reduced the difficulty for beginning gamers.

[65] Square was worried that western fans would find it difficult to adjust to the game's complexity due to not having played the previous two entries, so decreased the overall depth considerably.

The most notable changes in the PlayStation release are the inclusion of a full motion video opening and ending sequence, the ability to move quickly in dungeons and towns by holding the Cancel button, and the option of performing a "memo" save anywhere on the world map.

In Japan, a special version was available which included a limited edition Game Boy Micro with a themed face plate featuring artwork of Cecil and Kain.

[65] The abilities that were removed from the original North American release were re-added, while spells were renamed to follow the naming conventions of the Japanese version, changing "Bolt2" to "Thundara" for example.

Ordeals was added featuring powerful armor and stronger weapons for five additional characters, as was the Lunar Ruins, a dungeon accessible only at the end of the game.

[81] In December 2012, the Nintendo DS version of Final Fantasy IV was released for the iOS and Android (June 2013) mobile platforms, introducing an optional easier difficulty level.

[90] In its December 1991 issue, Ed Semrad, who gave it a 9, wrote that "Square has just redefined what the ultimate RPG should be like", noting the "spectacular Mode 7 effects, outstanding graphics and a quest unequalled in a video game", concluding that it "makes use of all the Super NES has to offer" and is "the best made to date!"

Ken Williams (as Sushi-X), who gave it an 8, said that it is "a totally awesome RPG", the "storyline is actually coherent and the plot moves along with a combination of speaking sequences and battles".

He criticized the "stylized" combat system and the graphics as "inferior" to Zelda, but praised how every "spell has a different on-screen effect" and the difficulty for being "just about right" where bosses "nearly beat you every time" unlike other RPGs such as Ultima where enough "adventuring" makes it possible to "trash" enemies "with ease".

He praised the story in particular, noting that, in a departure from other RPGs where the party always "sticks together through thick and thin", the characters have their own motives for joining and leaving the group, with one that "even betrays" them.

He said that it is like "following the storyline of a fantasy novel", comparing it to The Lord of the Rings and Man in the Iron Mask, concluding that, because "the characters often spoke up for themselves", he "got much more attached" to the party "than in any other computer game".

[3][4] In a 1997 retrospective, GamePro credited it as "the first game where a turn-based combat system allowed you to change weapons, cast spells, and use items during a battle, and it featured some of the most exciting villains to date".