NHF – new heroes for Heroes V 3.1.

psatkha, your calculator shows that a Seraphim is level 8.

There is a level 8 in the game. ;)

And by the way, you don't need to calculate castle creatures with the calculator, as the growth rate for castle creatures is determined differently. If you're interested, you can ask the esteemed comrade Nargott. ;)

Sincerely, Psatkha