How to make rakarth work

I've read a few posts already suggesting me to use the ranged units but I see little to no effect. The first tucking lizardman opponent steam rolls everything, archers don't seems to do anything, the ballista is actually horrible as well and monsters that I had just seems to do nothing as well. I've restarted this so many times only once getting the first enemy wiped before bretonnia came to wipe my ass with every other possible faction nearby.

I tried lokhir thinking it'd be similar but went to wipe every opponent without an issue.

More of a tilt post but I hate not being able to do anything with a specific lord