Quote Originally Posted by Max_Killjoy View Post
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There are plenty of ways that combat is dangerous and risky for RPG characters, and plenty of "opportunities" for setback and failure, that don't require shoehorning in hackneyed random "you hit yourself with your own weapon" or "you just happen to drop your weapon" events.
You are correct, in the sense that simply missing in combat is potentially life-threatening fumble as it allows an opponent to act for longer.

The corollary to that is that in dangerous situations, magic simply not being a surefire thing is sufficient to introduce much-desired risk into the game.

There are only two major reasons to add fumbles, or any other carrier effects, on failures:

1) to speed up play by preventing long chains of "nothing happens".
2) to create situations which wouldn't otherwise emerge from the game rules. For example, in combat, you don't need a fumble for the Fighter to drop their weapon, because a miss gives their enemy an opportunity to disarm them, creating the same result. But if swinging your sword at a wall, the wall is not legitimate user of "disarm" action, so under the simplest rules your sword could never be broken or fly off your hand. So a new rule needs to be added if it is acknowledged and desired that yes, if you swing your sword at a wall long enough and hard enough, something might happen.