Different Game Endings

Fire Emblem 7 actually has three different endings with changes in each. Here is how you obtain them:

Ending 1: The "default" ending. Complete one or fewer Kishuna chapters to obtain it.
Ending 2: A hidden ending with minor changes to the final boss fight, such as a different death quote. Complete two Kishuna stages to obtain it.
Ending 3: The hardest ending to recieve. It has major changes, including a different death quote from Nergal, new dialogue, and a new "Fin" picture at the end of the game with Nergal and his wife. Complete all three Kishuna chapters to obtain it.

*Note: The "Kishuna" chapters are 19xx, 22x, and 32x.

Secret Shops

Secret Shops are hidden on the maps and can only be found by a character with a Member's Card special item, which can be stolen from an enemy in chapter 19. These Secret Shops sell high-level weapons and even items to promote your characters.

Chapter 19 - One is in the clearing between the two broken walls above the room with the two treasure chests in the upper left corner of the map, and the other is behind a wall in the lower-right corner.

Chapter 21 - The empty room in the upper-left corner of the map.

Chapter 23 - There are two versions of this map. If the boss is Linus, the shop will be on the right side of the map, on the island. Otherwise, it will be in the trees above the lone house slightly left of center.

Chapter 29 - In the two-by-two square area left of the lone treasure chest at the bottom-left. You must use a warp staff to get there.

Chapter 30 - In the very upper-right corner of the map, among the trees.

Silver Card

In chapter 18x were there is a magic seal, have a thief steal it from the boss. The silver card will make the prices of items from shops cut in halve. NOTE: Make sure to steal the silver card before you break the magic barrier. You must be playing on Hard difficulty as well.

Control Enemy Units

Place a Mine anywhere on the field. When an enemy unit walks onto it, while they are taking damage, reset your game. When you continue your game, it shows the enemy being damaged again, and then you can control your enemy units. Use this to make them discard all of their items, retreat, or attack units that you want to level up. Note* Enemy units can only be controlled for one turn.

Keeping ring effects for more than 1 turn

If you wish to keep the effects of Nil's/Ninian's rings for more than one turn, have the affected character be rescued. This will allow you to keep the effect for another turn.