it's not at all necessary to start with Mages.
the fact that combat mages appear there is just a hero-related random event. most often there are just 16 regular ones. archmages can also appear.
it's easiest to start with Goblins or Archers. if you're lucky, you can defeat the armored units near Stephen's tomb. the main thing is to position your troops correctly and resurrect them at the right moment.
in general, I've finally found some time and will soon release a new version. so it's better to wait a little.
Added after 19 hours 56 minutes
When will the new version be released approximately?