Chapter 20 (Darkling Woods) sprites appear different on map than the actual unit. Some enemies are represented by a piece of Morva's sprite, while others are represented by an entirely different class. Even worse, units are sometimes simply not shown on the map at all.

These observations were made during the preparations for the chapter, specifically while viewing the map with "Formation".

Hero (tiny piece of Morva wing)

Wight bow (shown as Wyvern Lord)

Druid

Pupil

Sniper

Wight (sword)