Elephants

[RLucid]

Elephants were rarely used in Europe even when they could provoke a devastating effect, one time by Pyrrhus and another time by Hannibal. I don't recall any other usage of elephants militarily.

Think the Romans used Ele's to in early Macedonian war, where they used them as cavalry screen, like Hannibal (not the over-powered battle tank versions which chew up a whole army).

All the enemy need to do is get together some iron spikey things, bit like the barbs on barbed wire and your Ele's loose any offensive effectiveness (1 archer per Ele is not high fire density, and visible missile could be dodge by troops in open order).

So they weren't any good once opposition had some time to come up with a counter.