Ranger>Hunter>Multiattack, the Volley option: in-game it came up does it have to target everyone in the R10'? Also, is Multiattack classified as an Attack action allowing the use of Extra Attack? Past comment by #WotCStaff seems to indicate yes. @Dan_Dillon_1 @JeremyECrawford
— B Lynn (@DaddyDM) September 12, 2020
My recommendation is to only go by what Jeremy says, or what's in the Sage Advice Compendium.
Regarding Extra Attack, he lays it out here (for Whirlwind Attack, but same use case):https://t.co/5ArKWj2d3E
— HangDan's Joke (@Dan_Dillon_1) September 13, 2020
In summary: "You can use your action to…": is NOT taking the Attack action, which is required for Extra Attack to function. Volley is its own thing. #WotCStaff
— HangDan's Joke (@Dan_Dillon_1) September 13, 2020
What about the 1st question of do you target all creatures w/Ranger’s Multiattack or only those you choose? "You can use your action to make [an attack] against any number of creatures…"
You aren't forced to attack everything, you can choose.
— HangDan's Joke (@Dan_Dillon_1) September 13, 2020