I'm wondering about who to 6Star first, I currently have Athel, Martyr, Miscreated Monster, amd Apoth as my main team (with Elhain and one or two others who are 5 star but not using), I'm thinking Athel or MM first because they are fully booked and near max Ascendance (also considering Martyr in the back of my mind). But I am curious because I do need a farmer for brutal, but I don't know who to pick overall. Any advice/suggestions woul be very much appreciated. It's taken me awhile to get this far towards a 6star, so I would like it to be a strong choice, and preferablly one who will help me get my next 6star much quicker.

The way you are writing you know everything already :)

It would be Athel if you didn't have MM. You have Monster - you 6-star Monster :)

MM can farm campain and is useful in all other areas.

You will max Martyr, but not first because she's not as good as MM as solo campain farmer.

Disclaimer: I don't have MM and Martyr, and my Apo and Athel are level 1.

I feel like I should max Miscreated Monster, but I'm honestly confused, I hear Athel is a beast and can farm brutal on her own. So I'm not entirely sure now.

She can. MM and Athel both can farm brutal on their own. But MM is better than Athel in all dungeons except Fire Knight. When you have 10 level 60 champs, you will still use MM. You hear about Athel more often because many players don't have MM when they are choosing their first 6*.

Martyr is a god tier Legendary. Yes, maxing her will do a lot for your account. She needs Legendary books to reach her full potential, though.

Miscreated Monster is another game changer, in the Arena, and in dunegons, such as the Spider. He needs Epic books, though. In my opinion, he is not that great as a Campaign farmer, compared to Athel. As you have him booked already, he will serve you well too.

Athel is a great choice for a first *6. She is still my Campaign farmer even at account level 68. She needs books too, but only Rare books.

You will definitely want to eventually *6 Apothecary too.

Athel and MM are fully booked Athel is at max ascendance currently, MM at 3/5, Apoth is fully booked and 3/5 ascended I think, and Martyr has 3 books in her (turns out I had a couple laying around) and is 3/5 ascended.

I want to 6 star them all as my main team right now. Just trying to figure out who I should do first to help rush the rest of them along.

In my opinion, it would be Athel.

Mind explaining really quick as to why? Can she solo 12-3 brutal for farming food or something?

The basic point is that sooner or later, you'll stop using Athel as you get better champions, whereas MM and Martyr are great champions who will never become obsolete and you'll never stop using. Hence, if you take MM to 6* first, the idea is that you never bother to bring Athel to 6* at all anymore, basically skipping that step (saving some resources) and immediately going for long-term champions. It may be a bit more difficult in the short run, though, because right now you could definitely use a 6* Athel. And it also depends on whether you already have better AOE damage dealers than Athel today, or if you still depend on future shard pulls for that anyway. 

Edit: And yes, Athel can solo 12-3 brutal - SunnyRay is saying MM could too, though it would probably be less smoothly and slower. 

Well just want to add that the general rule of thumb is that you first take to 6* the hero that can farm 12-3 in sub 30sec.

And IMHO, the easiest to achieve that in that list of yours is Athel. She is also incidentally my 12-3 farmer, with average time of 27sec per run, and her record in 12-3 is 9sec.

And after you achieve that, you can get more "food" to take other to level 60 faster, and honestly I don't think you will need to replace her with anyone else for that sole duty. Unless you want to achieve sub 10sec per run, which I honestly think is just a vanity project.

Exactly this. As I said, Athel is still my Campaign famer, although I prefer to farm 12/6 due to higher XP gain, meaning lower Energy cost per food champion. She can get it done in 15-25 seconds, depending on Cooldown Decrease RNG.

Athel is a great champion for Fireknight and Spider too, becasue she has a 3-hit A1 with Weaken, and her A2 AoE hits like a truck. I am still meeting Athels in Gold IV Arena, and she was with me all the way up to Gold IV, until I got a better nuker. I only use Kael in Faction Wars now, since I have Frozen Banshee, who is much better in Clan Boss with her strong poison.

My Miscreated Monster (not maxed out yet, mind you) is built not as a Campaign farmer, rather as a shield generator for Spider, and Arena too, if I need stronger shields:

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