Power Break is useful, and for taking it down, any magic or physical attack will do. Casting Nul-spells helps dealing with its Oversoul version, or if the player has access to them, using Lunar Curtain, Shell, or Reflect will help in cutting down the damage. White Mages should cast Protect on themselves.
One notable Iron Giant was actually a Pupu in an Iron Giant suit sent to observe the residents of Spira. After attempting to translate the strange "fiend", Shinra brought Iron Giant to the Thunder Plains where he witnessed the Pupu emerge from the Iron Giant suit and leave the planet with the data it gained. After witnessing this Fiend Tale Ending, the Empty Heart team appears in the Fiend Arena.
[view·edit·purge]The mythology and legends of many different cultures include monsters of human appearance but prodigious size and strength. Giant is the English word, coined 1297, commonly used for such beings, derived from one of the most famed examples: the gigantes of Greek mythology.