Fortunately for Wolfe, there was no need to actually do Rank Seven damage to the target in order to break through their defences. Instead, you could do it by brute force, the same way that the Fallen Army had taught the world of mages to break into Wolfe's world. Thousands, or tens of thousands of smaller attacks, all at once.
That was going to stretch Wolfe's ability at mana control to the limits, but he was fairly certain that he could get enough smaller spells focused together to emulate a single spell near his maximum output.
The Pit Daemon was durable, but not a strong magic user, and it wasn't even using defensive magic yet, as if it didn't think that it needed it.
Or perhaps it couldn't use it at all, and it was just physically strong. It was even flying with its own wings, and not as the Succubi did, by using magic to supplement them.