Multi-target/AoE attacks follow special rules to streamline play: they do not miss or crit, and a single roll is applied to all targets. (Ignore (dis)advantage from conditions on individual targets—such as Blinded or Grappled—though anything granting you (dis)advantage still applies to your roll as normal.)
Multi-Target/Area of Effect (AoE)
Core Rules v2 p. 10
FAQs
1Can you Interpose against an area-of-effect attack?
OfficialCore Rules v2 p. 55
If one can be pushed out of the affected area, AoE attacks can be Interposed.
Related Rules
2Cones & LinesAdventuring / Movement, Range & Space
Range and ReachMagic / Targets, Areas & Saves