Fire Emblem: Shin Monsho no Nazo

The Japan-only remake of the third game and BS Fire Emblem, and the sequel to Shadow Dragon (itself the remake of the very first Fire Emblem). It does have a fan-translation, though.

Unused Items
Once again, the Torch. A rare item for use against fog of war.

Debug Map
There is a "debug chapter" of sorts that contains many interesting recruits, such as the otherwise unused Gotoh. You can also get some combinations not possible in normal gameplay, like Nagi, Samson and Arran. You can use Action Replay codes to get there, but you'll need beforehand to have a save on the blue save circles on the map.

Enter the following code and hold L while loading your Quick Save, and you should begin on the debug chapter.

Unused Dialogue
During Prologue 7, Katarina asks My Unit if there's somebody important in their life; usually My Unit responds that person is their liege, but there is an unused dialogue branch where they say that they don't know if there's such a person. Presumably this branch was removed because My Unit is going to become one of Marth's knights tomorrow and it would seem odd if My Unit doesn't want to serve their liege, Marth.

At the end of Prologue 8, there is an unused scene where Norne says goodbye to My Unit, like most of their other allies. Judging from the dialogue, it seems Norne was going to be playable in the Prologue, possibly if Ryan reached 0 HP.

Unused Playable Character
Gotoh is the only playable character in Shadow Dragon who isn't playable in this game. He gets an awesome appearance in Chapter 14, yet he has stats that are mostly inferior to his Shadow Dragon stats.