Boons of Chaos Requirements for Chaos Lords/Heroes

There are lots of very good boons, but some seem impossible to actually get. At least half of them involve winning a battle against another specific Chaos god, but all the other chaos factions gets wiped out pretty quick in any Immortal Empires campaign. Certainly long before you both have extra lords/heroes and have a chance to reach them.

I assume these requirements are far easier in the base campaign where all chaos factions start next to each other and small random chaos armies spawn from all the portals. Is there a way to generate chaos armies in Immortal Empires?

What do you guys think about Chaos Boons in general? I like that even the not so impressive ones are still something decent. The worst boons are better than pretty much the best Ogre names.