In terms of his army, he only has ifrits as flying units, but there aren't many of them. By the beginning of the second week, we can easily kill 9 Archons (30 defense for the hero) with one stack of archers + magic. Overall, this hero doesn't seem invincible. Of course, this is all based on testing. =)
But he needs to spawn further away from the Rampart. This can be achieved through reloads. Otherwise, he might spawn near the fort on the hill, upgrade his ifrits there, and combine them into one stack. I did that once. I tried it a bit just now.
Regarding the author's words, General Broc kills phoenixes and takes the healing scroll from them, which we then receive. That's all I noticed when playing like this.
I posted a brief walkthrough on maps4heroes, in the map's comments. I know that you receive a notification in your email for each comment.