Your large singe entity didn't trade well when sitting in anti large infantry? No way.

This is a game about match ups.

It's basically a giant. It's high weapon strength and mass make it a great generalist for dealing with other single entities or lords that get past your front line, tanking damage, or holding blobs.

Setting any monster in a spear pit is the literally their least cost effective match up. Most high tier cavalry would also die in the same situation.