The walking siege engines of the Cosmic Era
The Rocky Mountain Republic owes in large it's existence to a single limited run of primitive mechs, the Assault/Bombard Mech model 1.
T'was a great roar, milord, and the ground was rent and the horses took their bits in their teeth and there was much confusion. No magic could reach so far, and none of our magehounds scented wizards. We do not know the deviltry of the enemy, and for this we lost the battle.
A world where most people know a few cantrips and even non-magical people can help to cast spells. Which is just as well because the big spells can only be cast with the help of large numbers of people.Most large spells tend to protect borders and stop earthquakes as they can be done legally, but there are those willing to cast bad large spells s well.A major part of law enforcement in this world is preventing evil magic.