How to win with a “weak” Knight?

So, what should be used to fight dragons from the Magpie faction? The Phoenix deals approximately 25% less damage. Four Phoenixes with a Barbarian, with an attack stat of around 10, can defeat a red dragon in just one turn, but they probably won't be able to defeat a black dragon. To replace the effectiveness of four Phoenixes, you would need approximately 20 White Unicorns or about 70 Dwarves.