As I keep studying the engine code, I find hints on some planned things that were cut or not fully implemented (because game development).
I’m aware of many things like censored Nawar lines, disabled multiplayer mode, removed Glide spell and some other things being documented already so I’ll try to mention less known things.
For example, the game recognizes about thirty spells but in reality it had about ten more. One was probably deleted Glide spell, there’s something that looks like Dragon Frost spell (which acts like Dragon Fire spell but with a blue dragon head and probably frost damage). I can’t say much about the spells but considering the hints in the code there was supposed to be a completely different category of spells (normal spells have identifiers starting with 101500, paladin abilities have identifiers starting from 101600, those unknown spell IDs start from 101700 and seem to be attack spells only—maybe it’s for multiplayer mode?). For most of those there is no graphics except for one unknown spell: 
Or there’s a model 98 called Sparkles which looks like a stone naked woman, I don’t remember seeing that in a game (as well as roaches). Or a blue version of a dragon (which gives only 20-50 drachmas as a loot). If I ever get to rendering stage one day I should provide pictures.
I’ve also discovered some data related to the cut Wizard’s Whirl game. Sadly there is still almost no code associated with it beside some handling of the whirls that should probably appear at fixed points and hero and Erasmus should interact with them somehow.
So here’s the supposed background for the game:
Wizard’s Whirl alternative background
And there’s a set of sprites replacing the whirlpools with rather disturbing lips like these:
And I suppose Whirlwind spell would be the prize in this game (like Razzle Dazzle in the Hero’s Quest) instead of being given for free.