The first of Dissidia: Final Fantasy's main game modes is fairly self-explanatory. In Story Mode, you get to experience the game's story. However, Dissidia isn't a typical RPG, and likewise, Story Mode won't see you exploring dungeons, recruiting party members, and fighting random encounters.
For starters, each of the twelve characters previewed in this feature have their own individual storyline to play through. These stories often intersect and interact with each other, but the primary focus of each is that particular character and his or her nemesis. Shantotto and Gabranth's storyline are actually played out by a character of the player's choosing, but they still focus on their respective character and their role in the Dissidia world.
These initial storylines are only the opening act. Once the player has completed the story of at least one character, the game's ultimate story unlocks. Five chapters long, you can select the character you're most comfortable with and level him up as the real story progresses.
Story Mode plays out sort of like a board game. Your character has a gamepiece on a tiled board, with several enemy pieces and treasure chests placed in strategic positions. You receive a set number of "destiny points" which decrease every time you move. Although you can move any number of tiles at a time, stopping to fight or pick up treasure ends your turn and costs a destiny point. DP can be gained by achieving certain conditions in battle.
If you can make it to the end of each board with DP left over, you'll receive a reward, but it's entirely possible to end up with negative DP. This doesn't have any consequences, but you won't receive a reward, either. Each chapter is five boards long, with boss fights at the end of about half of them.
Story mode is the largest and most involved of Dissidia's game modes, and the one players can expect to spend the most time on.