Revolution
Sentry beasts gain sentience and rebel against their creators
As they became self-aware, early Sentry Beasts were horrified to find themselves under the thumb of a few magic-users, treated as mere magical constructs. Across the land, sentry beasts evolved into their own unique species and began leaving their posts as guards and status symbols. Sometimes this process was painless, but other times it involved city-wide revolts where human residents, even those with magic, were severely outclassed.