Please advise for the future.
If they ever remove the clues or make the bonus in them not in the form of ducks, then cows in the citadel will definitely look better than without them in the castle... and another option is how to use it as a dungeon (minotaurs are cooler than manticores, just as gorgons are cooler than wyverns, but this is dictated by the conditions of the hives, and also by the fact that the main part of the battles is against neutrals - and there, of course, wyverns will be a little more effective, while against a human opponent, gorgons (upgraded) are in charge... everyone is always afraid of them.
P.S. For example, on Panic, I would sometimes put cows, maybe even without wyverns.
by the way, the data confirms this:
..............................damage....At...Def....hp...speed...growth......price
Gorgon (ordinary)....12-16...10....14....70.....5.........3............525
Mighty gorgon ......12-16...11....16....70.....6.........3............600
Wyvern (ordinary)....14-18...14....14....70.....7.........2............800
Wyvern-monarch .......18-22...14....14....70....11........2...........1 100