Complex sentence: A possibility here could be that those that represent the heraldic insignia are corrupt, perhaps even unmerciful, due to representing such a high order in society that is supposed to protect people; yet the power it comes with causes corruption upon the person.
Split into simpler sentences: A possibility here could be that those that represent the heraldic insignia are corrupt, perhaps even unmerciful. This can be due to representing such a high order in society that has an aim to protect people; yet the power that comes with it can cause corruption upon the person.