Best way to kill abominations

[mattzu84]

I recently encountered adominations for the first time, and I was rather surprised. I was Ashen Empire and had trashed Mictan on one front and moved off to deal with pythia. Mictan then sieged my castle which blocked him off with a small army and 4 abominations. They couldn't heart my walls but trashed every undead army I sent. I finally had to bring my main offensive army over. Between my mages casting paralyse, my undead archers, too many destroy skeletons, and more turns than I thought combat could go one; I finally killed all four abominations. There has to be a better way to deal with them; hopefully a way acessable to ermor. Any insight would be great.