Cloud of Darkness (Final Fantasy III boss)

Cloud of Darkness is the final boss of Final Fantasy III and is encountered twice. It is first encountered in an un-winnable storyline battle after Xande has been defeated. At the very end of the game, after the party has traversed the World of Darkness, the Cloud of Darkness is fought again; however if the player has not freed all the Warriors of the Dark in the final dungeon before doing so, the final boss will have an unparalleled high defense stat and the heroes will find themselves fighting a losing battle.

NES Strategy
The Cloud of Darkness will usually only use a single attack, Flare Wave, which does 1,200 - 1,500 HP of damage to the entire party. On some rare occasions it uses a physical attack that ignores the character's Defense and will very likely result in an instant kill. Realistically one needs at least two high-level White Magic users in order to prevent the party being overwhelmed and destroyed by the damage from the Flare Wave, so once the player is able to bring the damage sustained by the party under control, the battle becomes mostly an endurance test.

The player should use all of their Shurikens (and make sure they reequip every round). The Sages can cast Haste on the Ninjas the first round (if the player possesses 14 or more Shurikens, it is not necessary to do that). Afterward, the party will probably have to cast Cure4 every round. If it seems like there is a round of respite, the player can call Bahamut. If the party runs out of magic, they can use Elixirs.

DS Strategy
One way of battling the Cloud of Darkness is just attacking the Cloud of Darkness' main body. An easier way, however, is to attack the left tentacle (the player's left) to rid the nuisance of using its Lightning attack. The right tentacle is immune to physical attacks, but not magic. The left tentacle is immune to magic and must be taken down with physical attacks. The tentacles seem to be weak to water; Tidal Wave is preferable to Megaflare in this case. The Cloud of Darkness can use Bad Breath to hamper the party unless the characters are equipped with Ribbons or Aegis Shields. Otherwise, only its physical attacks pose an actual threat (although they do not ignore defense in this version) until it starts to use Particle Beam (the same as Flare Wave from the NES version).

A Devout is highly recommended for this battle due to their ability to use high level White Magic, including Curaja and Arise, more often and more powerfully than the Sage. Also, they can support the entire party with Protect or cast Holy on the Cloud of Darkness. However, Protect can only be cast on one person per turn so that strategy is optional. Warriors can use their Advance ability to deal heavy damage to either the right tentacle or the Cloud of Darkness; Ninjas are useful for their Throw ability and they can also inflict massive physical damage to the Cloud of Darkness while dual-wielding the Masamune and Muramasa. It is preferred for Dark Knights and Dragoons to attack normally and only use boosts provided by Devouts and Bards, both of which are recommended to be in the back row. Bards can also use Sing with a Loki Harp for a more effective attack bonus. Black Belts however, can use Boost to save a Devout's turn.

Trivia

 * In Dissidia Final Fantasy, Cloud of Darkness takes on the same appearance it had in the DS version during EX Mode.
 * In the first battle with it the Cloud of Darkness is immune to nearly all attacks. However in the DS Version, a Dark Knight's Souleater attack and a Ninja's weapon Throw will deal regular damage to it. The battle will still likely end before enough Soul Eaters can be used to kill it though as the Cloud of Darkness will still deal full damage to the entire party.