Battles with neutral creatures.

The turn order is the same as in regular battles. It's just that the stacks of griffins are arranged differently at the start. But the algorithm is the same.

Did I list any unusual battles? Instead of stacks of griffins, there could be hydras, basilisks, warrior lizards on a swamp, harpies, etc.

What is the pattern in the fact that when attacking with one stack of griffins on a castle, my griffins go first, but if I add another army with a different speed to them, while leaving the griffins in the 1st stack, they no longer go first.

Thank you for the detailed answer; it seems that my post didn't make it clear that I would like to hear something with specific examples and a proper explanation.