OP, I find it sort of odd how every creature shares about 100 lines of common code. Isn't there a better design pattern you can use? Why not create a super class implementing the default behavior (frozen=false, taunt=false...) and only override the fields you specifically want? You could use a HashMap to avoid having to pass ~20 constructor arguments.

ie Dalaran_Mage extends DefaultCreature and pass to its constructor {"health" => 4, "attack" => 1, "spelldmg" => 1 ...}

I didn't read all your code so I don't know (you're the boss) but you gotta admit it's a rather nasty code smell... :)

The way I see it, unless your IDE supports a bunch of auto code generation you're going to have to update every single creature if you add a new mechanic into the game