Helo is an easy choice there, after that you can go back to 4 stars. With Helo, Nordri and Jouk you have a very nice 3 stack for tourneys, for events you add CGunnar and you have a pretty good stack there as well (an additional hit-3 would be perfect, like Karil or Yao)
I suppose Jott would be something new in your roster. Titan specialist, can be used for 4star rush, but not much besides…
Boril is definitely the better overall hero (in terms of where you can use him and in terms of impact on your gameplay), but as has been mentioned, there are even better 4 star counterattack heroes out there. If you are FTP it is definitely worth leveling Boril, since it can be a long time before you get S5 Azmia (or Ferant from CoK) etc. If you do spend money on occasion it is not too hard to get those, in which case I would go for the next S5 portal and try to pick up Azmia, level Jott in the meantime.
I tried to pull Azmia… but got multiple purple/green/yellow/red S5 heroes… Azmia just didn’t wanna show up!
I will level Jot and Helo, this will buy me some time to try again for Azmia… if she still doesnt show up, I will level Boril…
I need a counterattacker on my team for the heavy damage events.
Helo is useful also for challenge events, especially for higher stages.
Jott to be next.
Boril is useful for raid/war attacks, when fighting heavy-hitting defences (multiple AOE hitters, like Bertila or Khufu ).
I kind of agree here. Helo would be a quick level up and he is very useful in 3* events and in 3* tournies (especially as a counter for Tree and the like). After that you could go Boril to help with PVE stuff or Jott to help with titans, whichever area you feel could do with a boost.
One more vote for Helo The heal + cleanse come very handy. And then maybe Boril (especially for map, but also for war/ raids if you lack a better counter-attacker) Jott is good only for titans in my opinion.