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Phoenix, the new druid, will help the elf become an excellent Chaos Knight by increasing his spellcasting skills. Elves have a lot of mana, and education is often a reward (which includes mana attraction), so new druids slightly change the hero development strategy. And if you add the enchanted arrow to all of this, it's even better. And the old druids have good attack magic. In my opinion, the upgrades are equivalent.
