Unkillable Character In Challenge

[JudgeSmails]

What happens if I have an Archmage with Folariath's Robe and he gets challenged by a character without magical attacks?

[dabber]

Why the question?
No wounds are dealt in the challenge. As with all challenges, the rest of the combat goes as normal.

[JudgeSmails]

Forgive my lack of knowledge, but when does the challenge end? Does it continue until one of the units is wiped out or flees?

[dabber]

Challenge ends whenever they are no longer in combat, which in this case would be that- one side breaks.

[JudgeSmails]

What if one of the two sides gets wiped out?

[dabber]

Since you are talking unkillable Archmage, no one is getting wiped out, because either the Archmage or his challenge partner will not be killed. But one probably breaks when all his friends die, if not beforehand.

Is your real question about what other affects happen from a challenges? If so, I give my standard answer:
Challenges alter very little. An accepted challenge does exactly two things - 1) limit attack allocation and 2) allow overkill. Everything else continues as normal.