I don't think there is a worthy 6 star in your roster right now. 

When you are already in end game, some time around 2 yrs from now, you can 6 star Gnarlhorn and Berserker for doom tower hard secret room. 

I have to disagree. There is a champion worth 6 stars among them, the most underrated champ in this game: Bogwalker. He will bring your CB-team to a new level. Decr. attack on the A1 (chance can be booked to 50%), small version increase def buff on the A2 with an attack (chance for Warmaster mastery proc). In non-unkillable teams, decr. attack is the most important debuff vs. CB.

His passive reflect damage will help at Fireknight as well.

You should have made Bogwalker 6 stars instead of Diabolist. In a few days you will get High Khatun for speed, who is just better than Diabolist anyway.

I  disagree  with  JoinMe  this  time.

It  is  very  rare  to  see  me  disagreeing with  JoinMe.

Heroes  worth  6  starring  on  your  roster  include:

-  BogWalker

He  is  used  for  Clan  Boss  to  provide  Attack  Down

Attack  Down  is  a  critical  debuff  in  Clan  Boss  which  can  help  you  live  twice  as  long.

-  Witness

She  is  used  for  Arena,  Faction  Wars,  &  Dungeons to  provide  Shields.

She  is  used  in  Arena  on  more  of  a  tanky  arena  set  up.

-  Berserker  -  He  is  used  for  Arena,  D.T. Secret  Room  &  Faction  Wars  to  provide  Damage

He  can  be  used  in  Arena  to  help  counter  Force  Arena  teams.

Kael  &  Ninja  are  both  Magic  Nukers  and  they  have  weakness  vs.  Force  Affinity.

Berserker  is  Spirit  Affinity  - Force  Affinity  is  weak  vs.  Spirit  Affinity

-  SpiritHost  -  She  is  a  very  useful  hero  in  Arena,  Faction  Wars,  &  D.T  Secret  Room.

You  should  use  her  on  your  current  Arena  team.

Among those above, BogWalker is definitely an option to improve CB team. 

I thought myself about Berserker and SpiritHost too (mainly for Arena, though i'm using currently Warmaiden for all DEF-down instead of Spirithost for all ATT-up and it works well).

I'll check Witness. Didn't think she can be really useful for anything.

What about Armiger? Could be raising him, be an option among champs above? His Decrease Turn-meter on A1 and HP-dependent damage on A2 (with 2 Cooldown) looks pretty strong and useful even for ClanBoss team.

They are not wrong. But here is my opinion. 

Bogwalker is a very old school champion for cb. Honestly, when I am in the early game stage, I heard a lot of Bogwalker being good. I look at his kit, I am not impress. In my opinion, I would 5 star him but will not 6 star him. There are a lot of champions that are a lot better than him. Being hasty on 6 starring a champion knowing that you will replace it later on, is a waste of resources. Then later on, if I will feed him when I get a good replacement for him. 

Same thing with Spirithost. I use her 5 star but never 6 star her. She can be used in doom tower but like I said, it is an end game goal, that he should not worry for now. Hmm as for arena, maybe because I build def nuker team in arena during my early game, and I got Gorgorab very early, I never bother in using her, and there is High Khatun for speed lead. 

As for the cb, when I am in early game I never focus on lower cb at all. It just gives very little reward that you will not even feel you got a reward 😂. I researched and focus on the team that is viable for at least nightmare. CB below nightmare are not worth to focus on in my opinion. I will just put any good champions and do what cb I can do, until I have a good team that can do at least nightmare. 

You might find some team comps in youtube that features these rares in nightmare or ultra nightmare cb, but they require higher gear requirements that I don't think you have right now. At least higher quality of gears that you have. 

I will not focus on Faction Wars during early game. Getting at least stage 20 of Dragon is the goal. Just put what ever you have right now. It is not that you have very good gear that you want to use glyphs already. 

But since we have champion training going on right now and you think you have to 6 star someone, you can choose any the champions they mentioned. It is not wrong to 6 star them, I just feel that if you are in early game and free to play, you have to be frugal in your resources. 

I agree with Joinme, short-term many of those champs will help a bunch but those champs will soon be obsolete.

Armiger would be my next 60.

I  disagree with  JoinMe  &  Trips.

A  situation which  I  think  has  never  happened in  forum  history. 

The  Champion's  I  mentioned are  not  normal  Heroes.

They  are  much  more!

They  are the  heroes  Raid  deserves,  but  not  the  ones  people  need  right  now.

So  we'll  criticize them.  Because  they  can  take  it. Because  they  are  not  our  heroes.  They  are  Silent  Guardians,  Watchful  Protectors.  They  are  Dark  Knights.

 IMO you have some decent rares there but at 24 days in you're going to start getting much, much better champions within a couple weeks and I'd hold off on doing another six star still you pull a key rare like Frozen Banshee or Apothecary or whatever good epics you'll start getting soon. If I were in your place I'd be thinking about making several 5* champions rather than a 6* so you can get some value for now and use them as food later if/when you get better champs. A 5* Bog Walker in place of your War Priest would be a good upgrade for your clan boss team. Armiger is worth taking to 6* but he can do a lot of work at 5* for now. I'd also work on ascending Ninja.

Wait for High Katun..should be available in the next 3-4 days

I  think  that  you  have  a  few  champions  worthy  of  six  stars.

Bogwalker-  I  have  always  thought  of  him  as  underrated.  Has  a  good  chance  to  place  Attack  Down  on  A1-  that  is  good  for  a  lot  of  bosses-  especially  Clan  Boss.  Also  brings  Increase  Defense  (great  for  Clan  Boss  and  Dungeons)  and  Reflect  Damage  (good  for  Fire  Knight.

Graybeard-  This  is  a  good  CC  champion-  one  who  is  also  easier  to  book  than  someone  like  Ninja.  He  has  an  AOE  Freeze  for  a  Rare,  and  a  Provoke  A1  which  goes  well  with  his  Self  Counterattack  Buff.

Templar-  This  is  another  good  CC  champion  champion.  He  may  have  a  use  later  for  you  too-  you  can  use  him  later  in  your  account  against  the  Dreadhorn  Doom  Tower  Boss.  He  has  a  decent  Provoke  Skill  and  Decrease  Speed  on  the  A1,  along  with  a  pretty  good  passive.

Note:  All  of  these  champions  are  Defence-Based.  This  means  that  while  you  are  making  them  stay  alive  better  they  are  also  hitting  harder.

High  Khatun-  You  will  get  this  champion  in  a  couple  of  days.  She  is  great  for  Arena  as  a  booster,  and  can  be  used  in  Dungeon  Progression  as  well.

As  a  final  note-  I  do  think  Armiger  is  a  great  champion.  I  really  do.  But  does  this  account  have  the  level  of  gear  to  make  Armiger  do  the  things  he  does?  He'll  need  good  speed,  accuracy,  and  100%  Crit.  Rate.  Maybe  Armiger  will  be  better  off  waiting  for  later.

If you're f2p or a lowspender, you have a few options for 5*, but personally I wouldn't invest 6*s in anything you have yet. High Khatun isn't bad at 5*. but would be a solid choice for 6*. Armiger would also be a solid 6*, but as others have mentioned, you probably don't have the gear yet to take advantage of him. 

Might want to continue to build food and see what you get for the next 2x event!

Thank you all for very interesting opinions. Probably i'll indeed wait for High Khatun and raise her as the next 6*.

P.S. Yes, i'm f2p so far.

They  say  a  picture is  worth  a  thousand words.

Here  is  a  screenshot of  my  roster:

i

In  a  Sea  of  Legendaries,  You  see  random  Rares!

Fully  Ascended  -  Fully  Booked  -  Max  Level  -  Rares

WHAT?

It  isn't a  coincidence.

Everything I  do  has  a  reason.

Every  rare  you  see  in  the  picture is  a  champion  I  used.

These  heroes  were  critical  to  my  success.

In  Truth,  JoinMe  is  partially right.

Leveling  up  Rares  can  be  risky  because 1  day  you  will  have  roster  full  of  Leggo's.

The  rares  you  level  up  may  get  replaced.

I  no  longer  use  Bog  Walker,  BUT  you  can  see  Bog  Walker  in  my  picture Maxed.

There  was  a  time  when  I  didn't have  any  Legendaries.

There  was  a  time  when  I  was  stuck  in  Clan  Boss.

I  couldn't  4  key  NM.

I was  stuck  in  a  rut.

Bog  Walker  helped  me  get  over  the  rut.

It's  critical  that  you  understand  how  Bog  Walker  impacted  my  account.

People  see  a  roster  full  of  Legendaries,  but  they  don't understand how  it  was  created.

They  assume  it  came  from  money,  but  money  isn't always  the  answer.

1  -  Think  of  how  you  get  a  Legendaries hero.

You  can  get  a  Leggo  hero  by  pulling  a  Shard.

2  -  Think  of  how  you  get  a  Shard.

You  can  get  them  from  Clan  Boss,  Missions,  &  Quest.

3  -  Think  of  what  Bog  Walker  did  for  me.

Bog  Walker  helped  me  reach  the  max  NM  Clan  Boss  Chest.

Do  you  see  the  Cycle  of  Development?

-  I  started  with  Rares

-  The  Rares  pushed  my  damage  high  enough  in  CB  to  get  Max  Chest

-  The  Max  Chest  gave  me  Shards

-  The  Shards  I  opened  over  time  eventually gave  me  Leggo's

-  My  Roster  is  full  of  Leggo's

"Bog  Walker  helped  me  reach  the  max  NM  Clan  Boss  Chest. "

I followed your advice and raised Bogwalker to 6*, ascended and fullly-booked. Helped my CB-Team indeed.