There's only 2 with this wing. You could hypothetically be done with the entire wing in 8 matches. The first 5 are easy (3 regular difficulty bosses that unlock the cards + the 2 class challenges), but the last 3 are harder.

However, you could get more gameplay out of it with self-imposed restrictions, i.e. Amaz's play-only-as-priest or Trump's free-cards-only or Reddit's no-Alexstraza.