This article list various file formats which are used in Fire Emblem Fates. There are some useful tools that can be used to deal with those file formats.

AAC

Sound files. Any sound file converter can be used.

ARC

Archive files. Files with ARC extension are commonly found in various 3DS games, but they are in completely different format than Fire Emblem Fates' ARC files. ARC files in Awakening and Fates are used to store multiple files, mostly images and models.

FEAT can extract those files, while FEIF_ARC are able to extract and repack them.

BIN

Data files. For detailed documentation of this file format, see BIN (File Format)

Text files in m folder can be extracted using FEAT.

BCH

3D Model. Ohana3DS can extract the textures, and view the model.

BCSAR

Sound archive file.

BCSTM

Sound file. Most BCSTM file in the game contains 5 channels. In-battle BGM and map BGM is a combined of some channels in the same file. vgmstream can be used to convert BCSTM file to WAV and vice-versa. To split sound channels, Audacity is a good choice.

BFNT

Font file.

CTPK

Image file. ctpktool still has some trouble with CTPK file used in the game.

JSON

Live2D data in JSON format. Can be edited using any text editor.

LZ

Compressed file. FEAT can be used for decompression, while BatchLZ77 / DSDecmp4 / lzx can be used to recompress.

MOC

Live2D model.

MOFLEX

Movie file. Can be viewed using Moflex Player

MTN

Live2D motion data. Any text editor will do the trick.