I just completed a Werewoods delve with no casualties using the faction team but my faction info stats indicate best delve using faction team with no casualties = 0. I know that the troops can (and did) transform quite frequently, but this is by design and I have no control over this. Is a troop transformation being counted as a casualty in this instance?
You have to start the match and end the match with the same troops.
You don’t need perfect faction team run anyway. Just need a perfect run from normal to qualify. Should have faction team award? I did Silver N last week, when normal was imperfect, 500 completed but not with all troops. Got my faction reward, went and did 500 normal again because I lost a troop. That gave me perfect +faction team.
So that means it’s virtually impossible to get bonus for best undefeated delve and bonus for best delve with faction team in the same delve for this faction then? That’s super annoying since they built the transformation into each troop in the faction. 
I know you can use a non-faction team but as a shortcut to maximize bonus with fewer delves I usually just use the faction team to get all bonuses.
Yeah I know the feeling with limited daily delves, an extra delve per day wouldn’t hurt.
Not many factions beatable without losing something I guess though. Same with Mirrored Halls, I did it with Dwarven Gates.
Yes, that’s another really badly designed faction team. I don’t understand why the newer factions are so poorly thought out.
I once started a delve at a difficulty I hadn’t previously reached. One of my troops was changed into a Giant Toadstool by an enemy troop, and I still got points for no casualties. So I don’t know what the problem is here.