demon lord: both tayrel and fb are solid choices. accuracy is their most important stat so an accuracy or perception set wouldn't go amiss.

spider: my current advice to you would be don't. if you try to do every area of the game simultaneously, you'll end up spreading yourself too thin and failing to progress in any of them. for now, focus on building yourself teams for dragon, cb and arena and worry about spider once you've gotten a handle on those three. by then, you may have some better options.

dragon/ig: replace flesh-tearer with tayrel. if you can get to a point where noct can keep the team alive by himself, replcae vogoth too. fb is great for killing the boss, while giscard offers some great support options.

fire knight: see spider.

arena: just use tayrel. you're already building him for cb and there's no reason to build two champions when one can do both jobs.

next 6*: your next 6* should be tayrel, imo. he's an amazing debuffer who will help out your team in every area of the game. even if you don't end up going for him, ronda would not be a good choice. she's a great champion overall, but the most important thing early on in the game is to build up a team of champs with versatility and ronda has the exact same role as athel. both are magic affinity dps champs with very little utility outside that.

books: tayrel, hoskarul, and giscard are the three i'd be booking first, although zargala is a solid option as well. rare-wise, fb and soulbond bowyer are the only two i can see that are worth using; everyone else is just food. you might also end up using some rare books on armiger eventually.

one more piece of general advice : quit levelling your epics if you're not going to rank them up immediately. you could have built another 6* by now with the resources you spent bringing all of them up to 40.

dsamn good advise carpe ty

I know most of the content creators didn't comment much on the epics in this fusion but Trumborr looks really good as an option for CB, he has A1 weaken and leech (meaning you won't need to farm lifesteal so much) and then he has a ally protection and increase def. It is on a 4 turn so you have to keep that in mind. 

You have Yelagirna, I wouldnt invest too much in to her. I was using in faction wars due to her ress ability but she hits so weak it never procced. 

Where i can find new official promo code's, it looks that all code's are expired with New Year 2023. I am new player and any help is welcome!

Many, many thanks for the detailed reply - I've now evolved Tayrel to 5* and fully levelled him, and he already seems to make my Dragon 13 run reliable now. Just going to hold off 6* any one until CvC - I should be able to do two champions within the week - though I'm also going to add Frozen Banshee to my shortlist as everything I've read suggests I'm going to be making her a core part of my CB team for a long time yet. :)