“Heroes of Might and Magic V: Tribes of the East”

I'm curious to know about alternative upgrades for Assassins, Hydras, and Black Dragons. Maybe they'll just change their color, like they did with the Outcasts?:)
What ideas do you have? Share them:

The second upgrade for Assassins could make them a melee unit... and for Hydras, they could have only one head, but be much stronger and have a different name =))

This is just a guess, but you can come up with something even better.