I try to beat Fire Emblem Engage while killing the least amount of units possible. I hope you enjoyed watching. If you liked the video it would be great if you Subscribed and Shared with a friend.
Fun video! I did this same thing with three houses and it was also a blast thinking in a different light. (also golden deer is the route that requires the least amount of people to be killed if you’re interested)
I don’t think promoting actually reduces your exp gain in this game, so I’m not sure what happened with your Alear getting reduced exp after promoting.
Maybe reclassing to thief increased Alear's internal level to 21, since level 1 promoted thief is visually level 21? I'm pretty sure level 11 units get normal amounts of xp on ch10 but I could be wrong.