[HoMM V]9 Race - Swamp! Is it needed?

Judging by post number 62, you only manage to make a flying snake. So, that's how it should be: before the upgrade, it can only fly over part of the map, and after the upgrade, it can fly over the entire map! :)
And if you add wings to a basilisk, you'll get a dragon, and even a Chinese one. :)