Firstly, THAT IS A SHE. RESPECT HER! And you wonder why she is slaughtering your people. You offended her. [Hope I'm right here]
Secondly, do whatever it takes to surrender or end the war with her people. Give them your people, your cities, and your gildar if that's what it takes.
Third, raise or lower all the land surrounding this creature.
Forth, ally with this creature... perhaps have a son marry her.
Fifth, recruit some dragons to eat her. But only after she gives birth to a child or two.
Sixth, destroy what is left of her massive empire!
NOTE: Lapak is NOT a pre-defined NPC from my checks. She is randomly generated... and quite powerful! Wow.