You got enough. Hakkorn, Ursine Ironhide, Fayne, Steelskull, Reinbeast for 21, but I'd probably use Gnarlhorn in Reinbeast's place for 20. 

Hakkorn and Ursine Ironhide are pretty much guaranteed here- and will be a lot easier if they're fully booked. Fayne has to have high HP and Def as she's extremely squishy. 

For stage 20, an AOE provoke champion like Gnarlhorn will make the waves easy.

If I remember it correctly, the first time I succeeded in FW21, I two man the boss (I also use level 50 Taurus but died on the 2nd wave) with Khoronar and Steelskull.

But since you don't have Khoronar, just use Ursine and Gnarlhorn. They basically replace Khoronar's kit. AOE provoke of Gnarlhon will make the waves easy. Try level 50 Gnarlhorn first, if you made him tanky you may not need to 6 star him.

If you can't nuke the boss, you can follow the strategy I use:

At the boss stage, I believe it steals buff on its a2. So, buff only after he uses it. And at 30% hp (correct me if I am wrong) he will exchange HP from one of your champion, and you will have 12 turns to kill it.

The strategy here is not to fully heal your champion before the boss uses its exchange hp skill. 

I can't remember if it has side minions but if it has kill them first. 

When you are now hitting the boss, try to maintain your champions below 50% hp before he reaches 30% hp, then it will be easier for you to kill it after it uses its exhange hp skill. Steelskull's poison is enough to deal damage on the boss. Just make sure his a1 is fully booked for better chance of applying poisons. Also, Ursine's decrease attack debuff will help you tank the boss so better give this bear accuracy to land it.

appreciate  both  of  your  advises.  Very  insightful,  will  definitely  try  and  get  it  done.  Thank  you

I hate the damn health swap....I haven't eaten gotten past 14 on SW, my worst faction by far.  I finally beat ONE lol.  I'm going to upgrade the Bears soon, though I can't pull that unicorn Gnarlhorn ...

i

THANKS  A  LOT  GUYS  FOR  THE  TIPS.  managed  to  finish  my  last  faction  today  easily.  👍🏽

WOW congrats!

I need you guys to do a FW post with all your FW21 teams so I have a blue-print to follow.

I was thinking of doing that, but I got lazy 😅

I guess I could do the ground work and post what I have to work with for each faction on the ones where I am close.  

1 - done (High Elves)

4 - 60/63 (demonspawn, orc, undead, knight rev)

1 - 54 Sacred Order

3 - 52 Dark Elve, Lizard, Barbarian (should be easiest with Scyl/Kantra)

1 - 50 Orgryn Tribe

1 - 41 Banner Lord

1 - 39 Dwarf

1 - 36 Skinwalker

With the moving target of Doomtower changes, I am probably not going to have to worry about trying to beat floor 114 this month... so I will progress a little in:

1) FW

2) Get from S3 in tag to G1 (Lego Books!!!)

3) Upgrade gear to get UNM unkillable to 2key from 3key. 

3b) Prepare for affinity change on CB

Since OP (congrats again!) solved his question, I am hijacking the thread instead of starting a new one since I am lazy and this thread alread has attention...

My Barbarian Team (FW18 - 1star so far lol):

50 HK (unbooked, no masteries) 

60 Scyl (unbooked)

60 Kantra (unbooked)

40 Warmaiden (no masteries) 

50 Baroth the Bloodsoaked (unbooked, no masteries)