Good to know that Kalixis provide you with some challenge, although unlike other enemy bosses, the purpose of the chaos bosses is for them to cause chaos and bring ruin to both factions, but is not good to let them roam freely because in the end they will harm you more than what they helped you.
Well about the special effects of those wards: the unholy idol will heal all enemy units on the battlefield to 100% of their life each second for 30 seconds, so if you were taking down a boss at that moment, it will restore the life of the boss completely along with all other enemy units. The doom ward will make powerful beams from the sky fall upon all your faction's structures, dealing 5000 damage to them.
You got me there with the models. The thing is that the sky dragon model is the best dragon model there is all around the internet for the size it has, so I modified its original skin to a gray skin, which allows me to manipulate the color of the skin to have different dragons with different themes with a cool model, while avoiding to increase the size of the map too much with dragon models. The same thing goes for the model I used for emerald crusher, but the model used by the avatar of vengeance is truly one of my favorites, because of its outstanding mesh and animations, which is great, and it fits good in many themes; avatars, elementals, phantoms, revenants, energy beings and it is much better than the revenant model in warcraft 3.