There's too many of them in an elephant unit. For normal sizes, 6 elephants compared to 40 in regular units is ridiculously out of propoprtion. Imagine if the ancients had that ratio? 40000 men have 6000 elephants? Seems the only way to rout them unless you bring a long super anti-elephant troops (pigs) is to surround them with swarms of men, and you'll lose a ton in the process. Even when you rout them, they'll do some damage as you cut them down while fleeing, 6 routing elephants destroyed half of 2 of my cavalry units because whenever one fell down he'd take out 3-5 nearby horsemen.
Elephants should have 1-3 pachiderms in a unit.
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