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It's my turn to write about the choice between regular and alternative upgrades.
Hunters. Because invisibility and high damage output solve many early battles. Assassins are only strong with their poison attack at a distance, and even that is questionable. So, I choose Hunters for the most part.
Furies. With such high initiative, they will defeat many low-level creatures. Megeras, despite their high maximum damage and immunity to damage reduction, still lose due to their low minimum damage. I choose Furies.
Guardian Minotaurs will be useful for quick battles, and Overseer Minotaurs will be useful against Necromancers. So, they are balanced.
Dark Riders. What could be more important than completely ignoring defense? The ability of Swift Riders is always useless – they could deal more damage with a charge (like Knights). I choose Dark Riders.
Cave Hydras. Survivability is needed, as well as regeneration. Dark Hydras, apart from slightly increased initiative and questionable acid blood, have nothing to boast about. I choose the first option.
Shadow Lords. Let there be at least one ranged unit in the Shadow League. Night Stalkers, despite their simply charming appearance and high stats, are only useful in a few battles. Invisibility is enough for Hunters. I choose Shadow Lords.
Black Dragons are good against Dark Mages, and Red Dragons are good against heroes who rely more on brute force. So, the upgrades are balanced.
Conclusion: 50/50 between the upgrades.
Hunters. Because invisibility and high damage output solve many early battles. Assassins are only strong with their poison attack at a distance, and even that is questionable. So, I choose Hunters for the most part.
Furies. With such high initiative, they will defeat many low-level creatures. Megeras, despite their high maximum damage and immunity to damage reduction, still lose due to their low minimum damage. I choose Furies.
Guardian Minotaurs will be useful for quick battles, and Overseer Minotaurs will be useful against Necromancers. So, they are balanced.
Dark Riders. What could be more important than completely ignoring defense? The ability of Swift Riders is always useless – they could deal more damage with a charge (like Knights). I choose Dark Riders.
Cave Hydras. Survivability is needed, as well as regeneration. Dark Hydras, apart from slightly increased initiative and questionable acid blood, have nothing to boast about. I choose the first option.
Shadow Lords. Let there be at least one ranged unit in the Shadow League. Night Stalkers, despite their simply charming appearance and high stats, are only useful in a few battles. Invisibility is enough for Hunters. I choose Shadow Lords.
Black Dragons are good against Dark Mages, and Red Dragons are good against heroes who rely more on brute force. So, the upgrades are balanced.
Conclusion: 50/50 between the upgrades.