Would a monk's unarmed strikes count for Hunter's mark then? I thought they replaced weapon strikes but weren't actually melee weapons?

— Darkest (@AeonNightmare) October 27, 2018

Every attack in D&D is either a weapon attack or a spell attack.

If an attack isn't one of those types, it's the other.

An unarmed strike isn't a spell attack. It is therefore a weapon attack. #DnD https://t.co/aktyYdQI2o

— Jeremy Crawford (@JeremyECrawford) October 27, 2018

I understand what you are saying here for game purposes, but I think that the guiding principle is confusing. Couldn't you just as easily say, "An unarmed strike isn't a weapon attack. It is therefore a spell attack"?

— Jonathan Chown (@ChownJonathan) October 27, 2018

An unarmed strike is a weapon attack because the rule on unarmed strikes says they're weapon attacks. #DnD https://t.co/07BmPRNCcy

— Jeremy Crawford (@JeremyECrawford) October 27, 2018

D&D is a game of exceptions; an attack can be special and not fall into either category: weapon or spell.

The rules tell you if an exception is happening. For example, the grapple described on p. 195 of the PH is called a special melee attack, not a weapon/spell attack. #DnD

— Jeremy Crawford (@JeremyECrawford) October 29, 2018