Qm said

[Kristoffer O]

The problem is not one elephant or 5 elephants, but 50 of them.

I haven't seen this, but this seems to be what it is about. When you pass a critical mass of elephants there is nothing that can stop them and they become worth far more than the 150 you buy them for. Especially since they trample every routing unit, effectively eating up the entire enemy army, regardless of size.

Elephants are supposed to break easily, and devastate the own army if they do. But if you mix them with high morale heavy infantry, they do not rout as easily. This is thematically unsound: elephants that doesn't rout because they know that their brave human friends way back dont care if some of the elephants die or get poked by spears.

So in short: Elephants are fine at their cost as long as you don't get too many. At that time the game mechanics for trample might make them unbalanced. Especially if used with the silly tactic of mixing them with elites for better morale.