In a parallel universe people born with high affinity can apply magic directly on the material world, you can use magic to harm others at the expanse of risking magical feedback similar to the amplification of sound through microphone. For example, when you hurl a fireball at a subject, there is some uncertainty that the fireball will detonate before leaving your hand and the explosion gets worse when you attempt more potent magical spell. Suppose magic don't care about cause and effect, and it has infinite range then why there is no instant death spell which includes magical feedback despite numerous attempts?
Magical feedback explained: To manipulate magic, one has to siphon the magical energy from the surrounding and usually the amount depends on the user's affinity, then to materialize the magic energy into a hot plasma such as a fireball one need to make a hand sign which serves as a catalyst to strengthen and contain the plasma. But be cautious as there is an uncertainty for catalyst to produce magical feedback without warning, levitation do not requires catalyst so there is no feedback but people still get killed from falling at height also note that catalyst only apply when user is applying magic beyond oneself aka action at a distance ;D