What creature or artifact would you create? (Heroes IV)

Маахир
Ideally, a sea race with creatures like mermaids and sea monsters is missing.

If we're talking about a new faction, we need to start with magic or "non-magic." In short, a direction.
It's easier to fill it with units and write abilities. In terms of ideas.
The point is that in Heroes 4, each faction is unique, and we should stick to that.