Gigantuar is a mark in Final Fantasy XIII fought in Mission 54. To activate the mission the player must find a Cactuar on Archylte Steppe. One can be found on Eastern Tors, the bit of the Steppe guarded by Adamantortoises (one can sneak past them easily); on the hill of that area the party comes across a Cactuar that Sazh notices. After the cutscene, Cactuars have been released on the Steppe and can be fought as regular enemies. Defeating Gigantuar earns the player the Floraphobe achievement.