I made it, but his mouth won't open. I can't fix this.
The fix is simple; I compared the animations of the Tower hero and Agbet. Agbet was missing two animations, so I added them and wrote the effects.
If the head disappears, but the hero is still moving, it means I messed up the effects.
I re-uploaded the mods (adding videos) and updated the description on the previous page, comment #15
P.S. There are two videos in "an eye for an eye," and each has one hero. The first one definitely features Agbet, but I don't remember about the second one; you need to play the scenario to see. Different heroes are used in the two videos. I replaced both with Agbet.
Added 20 hours 17 minutes ago
I checked. The second video also features Agbet (his lines) and the animation is flawless. So, it was worth adding it right away.