Banner Lords are terrible. No legendary champ from that faction (Ronda will change this), and only 2 epics I would consider as good: Archmage Hellmut and Giscard. Other epics: Alaric, Arndulf, Lady Quilen, Masked Fearmonger, Lordly Legionaire.
Darkl Elves are close, I allready killed the boss, but no 3* yet. I think I just have to adjust gear.
Skinwalkers Cleopterix, Hippo Reviver, Steelskull, Fleshmonger, Ursine Icecrusher. Maybe they could beat the boss, but I can't reach him. Stucked at stage 18.
Other epics aviable: Fayne, Scabrius, Snorting Thug. And Yaga 🙁. Actually no Gnarlhorn from the rares. I think some control debuffs would help, and I could remove the Ice Bear from the team (the bear is only lvl 50 anyway). Have to pull Gnarlhorn again.
Lizards stucked at stage 17 with Rhazin, Skathix, Saurus, Broadmaw (50), Aox (50). Other epics aviable: Basilisk, Drake, Jizoh.
Knight Revenants. No legendary. Epics: Rector Drath, Sinesha, Thylessia (50). Rare: Coffin Smasher (50), Renegade (50).
I just pulled Doompriest recently. Couldn't level her yet, but she will join the team instead of Renegade. Maybe that's enough to do this crypt.