I am playing as a sorcerer -- mid-combat, when the sorcerer's turn came up, I did quicken spell + light, and planned on following it up with the spell scorching ray.
I see scorching ray is greyed out after I cast light.
According to D&D rules, I should still be able to use a spell slot with my action, if my bonus action was only a cantrip. I only expect the spells to be greyed out if I had used a spell slot for my bonus action!
See in this photo: Log in the top right shows all I did was quicken Light. Spells in the bottom left shows greyed out options.
I think the 5e rule is that if you cast a spell using a bonus action, you can only cast a cantrip using your action. So if you had cast Scorching Ray as a bonus action via Quicken spell, you could cast Light as an action.
Believe it or not, there is actually a video about this ! It a very recent comedy skit, but really includes the rule that says the Cantrip must be a Standard Action (for some odd reason; sort of a silly rule).
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Wow, I've been DM'ing it wrong in every one of my campaigns. I knew about the rule itself, I just thought it meant "if bonus action is a spell *that uses a spell slot*"
I definitely dislike the actual rule, haha, it's overly wordy and specific for no reason at all, I will continue with my rule in tabletop of "Your bonus action and action just can't both use spell slots"
It’s up there with “why can’t I use an action to do something that requires a bonus action”. Doesn’t make a whole lot of sense.
For sure : we simply use the core rule that you can cast 1 Cantrip and 1 Spell in a round maximum (no matter which of the two is a Bonus Action).
Also, while some Bonus Actions logically follow an Action (like the off-hand attack, Monk unarmed second attack), I would accept that an Action be used to do the types of Bonus actions that have no requirements.
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