If all straight lines extending from the point of origin to a location in the area of effect are blocked, that location isn’t included in the area of effect. To block a line, an obstruction must provide Total Cover.
Which to me says that in 5.5e, Cover does provide protection against a spell like Fireball unless the spell explicitly says otherwise, regardless of how it was meant to work in 5e.
I haven't read the new PHB with that much detail as I'm playing 5e myself, but I guess that would fall on the DM (like everything).
I would argue that with 5e rules you can't hide behind a rock to avoid a Fireball, but with 5.5e you can just based on that text. A Fireball is an explosion originating from a point. You might say things that are not on direct trajectory from the point of origin are not hit.
2014. https://www.dndbeyond.com/spells/2102-fireball
2024. https://www.dndbeyond.com/spells/2618887-fireball
Is there a mechanical difference with "goes around corners" removed?
I am wondering if "goes around corners" was intended to mean cover provides no bonus to your dex saving throw....
The mechanical effects of "goes around corners" were never super well-defined, which may be why it got removed.
The 5.5e rules on AoE spells say:
Which to me says that in 5.5e, Cover does provide protection against a spell like Fireball unless the spell explicitly says otherwise, regardless of how it was meant to work in 5e.
pronouns: he/she/they
I haven't read the new PHB with that much detail as I'm playing 5e myself, but I guess that would fall on the DM (like everything).
I would argue that with 5e rules you can't hide behind a rock to avoid a Fireball, but with 5.5e you can just based on that text. A Fireball is an explosion originating from a point. You might say things that are not on direct trajectory from the point of origin are not hit.
Edit: wagnarokkr beat me to it.