War Chariots and Quetchas are possible candidates???
I'd be very surprised if they get any votes.
Anyway, theres quite a few candidates for me. Keshiks, Ballista Elephants, Carracks and Jaguar all prove quite useless in most situations. However Carracks and Jaguars have a really potent use in the right situation.
The real candidates for me are Bowmen and Phalanxes because they retain non existing practical bonuses on top the normal unit in all situations.
Now the bonus is there in theory it just wont matter cause its practically redundant.
Bowmen gets a small bonus vs melee. In practice normal archers are allready better than warriors anyhow and a bowman still loses to an axe unless it defends with an extra bonus of 20%. It thus has a very limited defensive use vs axe IF one cant get axes himself.
Still, a phalanx is somehow worse. Now one can argue it gets a hefty bonus vs its only counter and thus is the dominant unit in the classical era.
This is theoretical crap again however. In practice a reasonable player that can field phalanxes can and will also field spears. A 3-4 to 1 phalanx/spear group will get virtually no bonus over one with mere axes. And ofcourse the typical counter used by the AI is axes that stand quite nicely even against phalanxes. Conclusion: a bonus with ultra limited scope and practically zero effect.
Therefore, phalanx gets my vote especially considering they stand for the core component of Alexanders invincible at their era armies that were used in the most awsome conquest in history.
Obviously game designers disagree as they nerfed them in BTS. Perhaps i am missing the obvious but i just dont see how str 5 spears are as good as pre nerf redcoats/cossacs. Maybe they thought they are too much a threat to HA.

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