I'm playing through the campaign, now, and I'm noticing now that the AI leaders get some pretty busted units from Quest buildings.

I've thought something was amiss in the past but I've seen it first hand this time. Dark Elf leader walks up to Mausoleum and gets 10 minotaurs + 1 Minotaur king. Just, instantly.

I guess the devs thought the AI needed a boost since they can't conceivably know and act on a randomly generated quest... but sheesh that reward is really good.