The animations are as follows, starting from C99058:
Byte 1: Weapon Type
Byte 2: 01* or 00**
Byte 3: Animation#
*01 if using a normal weapon.

To designate an animation:
Look at the Battle Animation Pointer in the Class Editor.
put in 0x8(six byte address) to point to the address where
the animation is listed at.

**To make a custom animation for a certain weapon, take Eliwood's:
84 00 04
If Eliwood uses the Durandal (item #84), he will use animation #04.
You have to put a 00 in the middle instead of 01, so the game
doesn't get confused.
You can also do this for characters that can use the Ballistas.

To make a chain of animations:
Each set of an animation takes up three bytes, and to go to the
next animation, you must separate them with 00.

Example:
00 01 0F 00 09 01 10
Lyn uses her sword animation when a sword is equipped,
and the next animation is Lyn when she's disarmed.

To separate animation chains, you must add a set of five 00s.

Example:
00 01 01 00 09 01 02 00 00 00 00 00 00 01 0F 00 09 01 10
Eliwood comes before Lyn does; but to make sure animations don't
collide and screw up the game, they have to be separated.

Using empty space near the end of the ROM, it is very possible
to make something similar to the Master Knight class from the
Jugdral saga! At the very least, you could make Mage Fighters. :3