The better answer is - don't build souldrinker. He's terrible :)

It is difficult to say, really it depends on your other stats. If he has 100k HP and 1.1k Defense, you likely want to up that defense on his ring. If he has 4.4k Defense and 21k HP, perhaps HP would be a good pairing.

My main thing I'd like to mention is to warn against equipping unleveled gear on champions ever. If they roll poorly, or you have better gear you want to use, you now have to pay silver to remove the gear. Try getting all gear to first 8 to see if it rolls well, then usually 12 prior to equipping it on any champions. You'll save yourself tons of silver, and hassle. GL!

i pulled him about a month ago and hes been in my vault since.

but i guess if u really want to build him then just go all out attack and hp based.

ring is usually the last piece I equip.  Build your middle row, then your top row.  Then it's either banner or amulet.  

when you get to ring, get the attack, and whichever sub you are poor on at that point!

once you need only a ring, what do you need more? Hp or def?

Ok, thanks a lot for your input. I think, I should give you more information of my situation. Actually this is my best squad of Demonspawn:

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You see, I'm a beginner, or maybe Middle Ager, and the question is: what is best to come forward. Now Soulkeepers (50) situation is the following: 

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I thought to build him firstly for stronger FW. I read about his great bombs he releases when being killed or the bomb that detonates after 3 turns. Strange to say that I didn't saw this unto now, so maybe I have to change something, or it is a must to have with him also Shaman?? 

But he was praised for this skill. And I like his outlook too - this dragon looks great, right? :) 

Thanks a lot for your commentaries - I try to be a good scholar :). And I'm aware that I have a lot of missing information to get a better look on the game. So every mention is positive :). 

Shaman is also terrible. Don't build her. Both her and Souldrinker are worthless.

Magnarr and Achak on the other hand are very good. Build them instead.

I disagree, I have a fun team I occasionally use in G5, if you don't have block buffs or cleanse I will use Kymer, Shazar, Cardinal (stoneskin) and Souldrinker - with revive and reset loads of bombs 🤓

there is nothing wrong with taking a few epics to 50 if its helping you progress through and farm the earlier stages of factionwars, but champs like souldrinker and shaman wont be hugely helpful for you as you approach the end of the factionwar stages, so its not really worth investing and getting them to 60 because they dont hold much use in other areas of the game either. but again nothing wrong with using him at 50 in factionwars, even at 60 he wont progress you much more.

Not particularly helpful advice for a newer player, though :)

Very true,  but if a newbie gears him right he could drop 4 bombs which could win a few arena battles

ok, thanks a lot for your input. Now I have this dragon and I am keen to see him dropping the bombs, even only for FW. Why doesn't he do this?? Above you see the setting I gave him.

Or is he doing this only in Arena fights?

Unbooked he only places bombs 75% of the time when using his A3, and the bombs have a 3-turn duration, which is stupidly long. The reason he has utility in arena is because of his passive, which requires him to die - and also, likely is only unlocked by ascending him.