Some spells like magic missile and scorching ray can strike a target multiple times. I recently had cause to consider using a damage spell to disrupt an opponent's spellcasting - and realized I'm not sure how multi-hit spells and concentration checks interact.
How many Concentration checks should a spellcaster make if he's struck with multiple hits from a single spell during spellcasting? Should the damage from the spell be totaled for one big check? Or should each hit force a separate check, giving multiple chances to roll low?
If you are affected by a spell while attempting to cast a spell of your own, you must make a concentration check or lose the spell you are casting. If the spell affecting you deals damage, the DC is 10 + the damage taken + the level of the spell you're casting.
This particular rule may complicate things, or simplify them, depending. It might seem to override the Injury sub-heading we're probably all already familiar with.
The accepted answer will probably be the highest answer in this hierarchy:
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