tell me, will these heroes simply be added to the main ones? or is this some kind of seasonal supplement
Pretty cool! Where did you get? 
3 heroes will be added in 1.8 to the regular heroes according to beta notes. So I suppose they can bet gotten from summons and training.
There was 5 new heroes, so one of them is the monthly. No idea what the 5th is for.
I want her so bad.
I don’t need her and i don’t know what she do, but she is just to cool.
Slowly but surely I’m getting my Training Camp to lvl 20 
, they look exciting.
PS.: - 1 on the Russian language not understanding anything…
as far as I understand in the game, the most interesting character of the three is Obakan. According to the characteristics, he is similar to Athena. he removes 44% of armor and still counter-attacks 115% and 5 turns
Red, except for damage, imposes on the closest allies 24% mana regeneration and 63% defense for 5 moves
purple girl deals 375% damage to one, removes buffs and gives the closest allies protection from darkness 94% for 5 moves
Obakan is also fast, middle girl, red slow
Any translation on the specials available?
You can view them in beta in English
the last two are the heroes of the month. they have very strange specializations
Purple deals 215% of the target’s damage and the next, summons the skeleton with 20% health and 15% attack from the hero
blue, deals 355% damage to the enemy, which gets -100% healing for 4 turns. can not be blocked. The hero gets 94% protection against ice on 4 moves
Humor me in how you do that please (read in english)
When i could get in, they were wrirten in English
These heroes are still in Beta testing; I doubt they were supposed to be released to the Forum yet. 
Oops didn’t realize this was the open forum