Silhouettes

So trying to figure out how the game makes the blacked out silhouette of Sabin's sprite on Mt. Koltz so I can utilize it for other events. Looking at Mt. Koltz on FF6LE it shows his palette as 6 instead of 0, but when i change the npc palette to 6 elsewhere, it just makes the character all ghost-looking. I am assuming it has to do with how the sprite is loaded but i can't seem to find the information on how to discern how the npc data is broken down, just merely where it's located (and unlike the event dump, i can't figure out where it ends either.

to simplify for anyone daring to try to help my feeble mind, the offsets for sabin on mt. koltz are
$C4/2D90 and
$C4/2D99

maybe if no one wants(or can) to answer this directly, sending me to a suitable thread/article that explains the general hex break down of the npcs i'd appreciate it. thanks for your time either way.