How does someone brace for something like this exactly? Maes understood his own ability, had seen various skills of alchemy performed prior to his arrival here, and had witnessed shape shifting once. However, it was nothing like this and it didn't really prepare you for it either. His image of a lion was all off too, but mostly because he had a hard time combining the idea of a lion with something mechanical.

Although, to Shiro's credit, the mechanical lion he transform into is much cooler than what Maes had been picturing. Maes looks stunned, but not necessarily freaked out (thanks to the heads up). He's certainly grateful to be seeing this now as opposed to being shocked by it in the middle of a dire situation or something else. He does need a minute to process and says helpfully, "Wow, that's...intimidating."