Role-playing Games Stack Exchange is a question and answer site for gamemasters and players of tabletop, paper-and-pencil role-playing games. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I know that blasts require LoS in 4e and that bursts require line of effect between the target square and the creature using the power but one my players asked if a burst would hit diagonally around a hard corner. My first thought was a hard no, but then remembered reading somewhere about bursts "splashing" around corners decided I needed some clarification. What are the rules for burst attacks and corners?

share|improve this question
up vote 10 down vote accepted

From my reading of the PHB, both require line of effect from their origin square, and neither require line of sight (p272):

A blast affects a target only if the target is in the blast’s area and if there is line of effect from the origin square to the target.


A burst affects a target only if there is line of effect from the burst’s origin square to the target.

You are probably remembering a rule from 3.5 that allowed spreads to do exactly what you describe. But 4e is a bit simpler; you only check whether there's line of effect from the origin of the spell. (I'm sure there are exceptions, but those will be explicitly called out.)

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.