Fire Emblem: Shadow Dragon Cheats - Nintendo DS

Unlock Gaiden Chapters
Chapter 6x - Have fewer than 15 characters at the end of Chapter 6.
Chapter 12x - Have fewer than 15 characters at the end of Chapter 12.
Chapter 17x - Have fewer than 15 characters at the end of Chapter 17.
Chapter 20x - Have fewer than 15 characters at the end of Chapter 20.
Chapter 24x - Have Chiki die, no Falchion.

Unlock Sound Room / Story Viewer
Complete the game once.

Official Hints
When you enter an arena you can see how much gold you need to wager to cover the bet on a fight. The bet changes based on the strength of the fighter your unit will face in battle. The lower the bet, the better the chance that you will be able to easily dispatch of your opponent, earning you money and experience. If you're worried that a proposed fight will be too tough for your unit, simply back out of the arena and reenter. Repeat this process until you come across a fight with a bet low enough for your tastes.

When you finish chapters 6, 12, 17, 20 and 24, you will automatically unlock optional side quest chapters if you have fulfilled certain conditions. To unlock the first of these after chapter 6, the number of total units in your army must be 15 or less including Marth at the time you complete the chapter.

In Chapter 3, send Caeda to a space adjacent to Navarre's and initiate a conversation with him using the special Talk command that appears. Remember, it has to be Caeda. Approaching him with any other character won't do the trick.

Don't forget to talk with villagers from time to time.

Make sure to purchase rare weapons in Chapter 8.

In chapter 8, there are multiple armories and item vendor shops on the map. Here you can find rare and powerful weapons such as Silver Swords and Wing Spears for sale. These weapons will make encounters in the coming chapters much easier, so be sure to make a few purchases before you seize the castle gate and end chapter eight!

You never know what you might gain from talking with the people of the land. For example, in Chapter 11, you can recruit a powerful ballistician by the name of Jake to your team, but only if you talk with his sweetheart, Anna, first. Talk with Anna by visiting the house east of the lake in the village on this map. Only once you've done this can you Talk to Jake using Caeda and recruit him to your cause.

Special Characters
Perform the actions below to recruit special characters:

Athena (Myrmidon) - Chapter 6x / Talk to Marth
Etzel (Sorcerer) - Chapter 17x / Clear the chapter without killing Etzel
Horus (General) - Chapter 12x / Clear the chapter without killing Horus
Hymir (Warrior) - Chapter 20x / Talk with Marth
Nagi (Mamkute) - Chapter 24x / Clear the chapter

Recruiting Units
Perform the actions below to recruit additional units:

Alan (Paladin) - Chapter 16 / Visit the village to the left with Marth
Astria (Hero) - Chapter 13 / Enemy, talk with Midia
Banutu (Mamkute) - Chapter 7 / Visit the village with Marth
Beck (Shooter) - Chapter 13 / Visit the village with Marth
Chainy (Commando) - Chapter 16 / Enemy, talk with Marth
Chiki (Mamkute) - Chapter 19 / Enemy, talk with Banutu
Daros (Pirate) - Chapter 2 / Enemy, talk with Marth
Dua (Mercenary) - / Finish Chapter 3 with 10 or less Units
Ellis (Cleric) - Chapter 24 / Automatically from the start
Est (Pegasus Knight) - Chapter 18 / Enemy, talk with Marth
Gato (Sage) - Final Chapter / Get it at the start (Only if you didn't go to Chapter 24x)
George (Sniper) - Chapter 9 / Visit the village with Marth
Gordon (Archer) - Last part of tutorial / Enemy, talk with Marth (Automatically from the start if you're playing hard mode)
Jake (Shooter) - Chapter 11 / Enemy, talk with Sheeda, must have visited village where Anna is (In same Chapter)
Kashim (Hunter) - Chapter 2 / Enemy, talk with Sheeda
Katua (Pegasus Knight) - Chapter 14 / Enemy, talk with Marth
Lawrence (General) - Chapter 20 / Enemy, talk with Marth or Sheeda
Linda (Mage) - Chapter 11 Visit the village with Marth
Machis (Cavalier) - Chapter 4 / Enemy, talk with Rena
Maria (Cleric) - Chapter 10 / Enemy, talk with Marth
Marich (Mage) - Chapter 4 / Visit the northern village with Marth
Minerva (Dragon Knight) - Chaper 10 / Enemy, talk with Marth, and must have recruited Maria
Navarre (Myrmidon) - Chapter 3 / Enemy, talk with Sheed
Norne (Archer) - / Finish Prologue IV with 4 or less characters in the party
Paola (Pegasus Knight) - Chapter 14 / Enemy, talk with Marth
Quatra (Knight) - Finish Chapter 3 with 10 or less Units
Ricardo (Thief) - Chapter 6 / Enemy, talk with Marth or Julian
Riff (Priest) - Chapter 1 / Visit the western village with Marth
Roger (Knight) - Chapter 8 / Enemy, talk with Sheeda
Samson (Hero) - Chapter 16 / Visit the village to the right with Marth (Can only recruit either Samson or Alan, not both)
Trim (Fighter) - / Finish Chapter 3 with 10 or less Units
Unil (Mage) - / Finish Chapter 3 with 10 or less Units
Wendel (Sage) - Chapter 5 / Enemy, talk with Marth or Marich

Underpowered Army
Finish Chapter 3 with fewer than 10 units and you will recieve help from Unil (Mage), Trim (Fighter), Quatra (Knight), and Dua (Mercenary).

Infinite Money and Exp
Note: This trick works best with Marth and Caeda (after promoting her to Dracoknight). Any unit should be able to pull this off as long as you're willing to devote the time.

Required:
1. Any Chapter with an Arena and Venders
2. An available savepoint
3. At least one unit that can use healing staffs (two if early in the game)
4. Enough money to make at least one Arena wager.

Clear the map, but don't seize the endpoint! Move your units over to the area with the Arena/Venders, then save the game. Enter the arena once or twice (depending on unit strength). Heal your unit with the healer(s) and end the turn. You get experience as well as cash at the end of each battle and your healers gain exp from healing. With the venders right there, you can buy all the staffs you need to keep it up as long as you like. You can repeat this ad infinitum.

Easy Levels for Gordin (Archer)
In Chapter 1 (Marth Embarks), get as many bows as you can and give them to Gordin. Next, you have to kill every enemy on the map except for the boss. Put Gordin in a space where Gordin can hit the boss but the boss can't hit you. All you have to do is keep Shooting him. Every time a shot hits you will get experience. Repeat this until you have leveled up Gordin. You may need to buy more bows.