I am sorry to complain but this spell doesn't show up in my attacks if it is supposed to be there then please fix it. If not can someone explain why it doesn't need to be there?

Click on "Customize"...and then check the box labeled "Display as Attack".

It works just fine.

thank you

-livybell

This spell is meant to be a reaction to being attacked. Therefore it is only activated when you take damage.

is this spell suppose to be available for blood hunters?

ok

Is there a way to make this spell available to other classes? My DM allows it to be used by a wizard in our campaign, but he cannot add it to his list.

Homebrew a new spell that looks like it, and add it to the wizard class list. Then as long as you're in the same campaign you don't have to share the homebrew and the wiz can see it

It's not under Attacks, it's under Reactions. It's only something you can do in reaction to being attacked by another creature. 

Can this spell be used as a normal spell or can it only be used once a day?

Can this spell be used as a normal spell or can it only be used once a day?

If it is a spell and not a racial trait, then it can be used as many times as a player has spell slots. If it is a racial trait, then just follow whatever the racial trait says 

Hi

Question that I can't find the answer to anywhere.  If I am fighting a monk that uses Flurry of Blows, could I used Hellish Rebuke after the first attack does damage or do I have to wait until they're completely finished with all of their attacks?

You can cast it immediately after the first attack does damage. As per the spell it is a reaction "which you take in response to being damaged by a creature within 60 feet of you that you can see".

Since each attack is individual in your example of flurry of blows, they each have their own damage roll. Given that, theoretically you could knock the monk unconscious after the first attack and avoid the other two by using hellish rebuke.

Hope that helps!

Will Hellish Rebuke hurt the caster if they are being grappled by the one on fire?

Take the Warlock Initiate feat... this will give him access to a level 1 spell and two cantrips. 

Or just homebrew a spell and copy Hellish Rebuke that way.... just make sure you make it available to the wizard in the tags

i wish it was for sorcerer's

If a PC casts Shield as a reaction to a spell attack, and it fails and the attack hits, they can't use Hellish Rebuke in response to getting hit on the same turn, right?

Quote from FeatsaPizza >>

If a PC casts Shield as a reaction to a spell attack, and it fails and the attack hits, they can't use Hellish Rebuke in response to getting hit on the same turn, right?

 You only ever get at most one reaction per round. So no, they cannot.