Arco's get Elephants, Cheap Hoplites, Priestesses (of course), Mystic (Blood anyone?), and Astrologer with 3 in Astral plus a random and of couse they get the Natarajah pretender (Caelum too; I think Alex likes the Natty a little too much

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They have huge advantages if you play certain strategies and are solid performers all around. Even Last night when I tried a Turmoil 3, Luck 3 Crossbreedothon/Lucky Arco they were able to pump out very decent armies (with -21% Income no less) and mystics/astro/priestess's every turn.