Spoliers
The first chapter of TSOD:TSE takes place in Madison.  It introduces the main character, Darcondia.  Darcondia is the adopted child of DarcTagnon and is the subsequently in line to become king behind his older brother DarcKegen.

Of course he receives a lot of slack because of this and feels that he must constantly prove himself to the other members of the royal family.  Strangely enough his brother, Kegen, is Condia?s only peer who respects him as an equal.  

In an effort to prove himself to Emperor Tagnon, Condia enters the Trials Championship in an effort to earn the rank of Supreme Guarder.

The new type of battling is introduced; a mix of card battling and Classic RPG battle style.  Basically, it is up to the player to decide exactly how they want to battle.  You can choose to focus on straight attacks and your own special attacks, or you can use the card to summon defenders to the field in your stead.   Obviously, in the beginning of the game, you don?t have very many cards, so you are dependent on your own skills and powers.   However, as you move through the game, and collect more cards, they will become and integral part of battling.

Darcondia is sent to the Meridian Desert to practice fighting the relatively weak creatures.  However, as it turns out, he is sabotaged by the son of General Einhold, Fate Einhold  another jealous peer of the royal family.  To Condia?s rescue, Kegen arrives and together they must defeat the Einhold Syndicate.

When Darcondia returns to Meridian, he decides to continue the Trials and officially enters the competition.  All together, there are 50 levels of varying difficulty.  The Trials are single player only, so you can?t fight alongside Kegen.  In fact, he is the 2nd seed so you have to fight him in the semifinal.  General Einhold is the top seed.  After defeating him you can choose to play the doubles championship.  Be warned, this is many times more difficult than the singles.  This is for advance players who have collected a full deck.  This is the end of the first chapter.

After returning to the castle, Tagnon gives you a mission to infiltrate the Madison base and eliminate the leader, Boss Maximillion.  However, you will need all sorts of special equipment to handle this enemy.  So you are first sent to the Infinity Isles to rendezvous with Cassidy Lunas.  Her and her baby brother, Jonas, are spies for Meridian who are staked out in the Northern Infinity Isles.

The isles are very dangerous because they are home to some of the creatures that live there.  There was once a thriving village there, but now there are only monsters.  This is why Cassidy is camped out there, because no one in their right mind would even bother traveling to the isle.
She and her brother are stationed in the underground chambers and only surface to leave the island, or to collect food.  

Cassidy and Jonas join your team for the trip to the surface. One thing that is apparently obvious is that the monsters are getting stronger. Cassidy points out that something is causing the creatures to react.  After securing the supplies, you are attacked by an awesomely powerful creature. Defeating it causes the second part of the game to come to a close.