The rules of football /soccer are made by the FIFA. The referee is the one who adjudicate them in the field. It's not the same.
Which rules are you talking about?
We have no rules regarding the "helpless" condition.
The referee can't make up rules on the fly. In fact, he can't make up rules at all.
Which rules? 5e? It clearly describes helpless being "cdgraceable".
Where?
The rules state that you can CdG unconscious creatures, that, in fact, are helpless.
Read them again.
But it does
not state that you can CdG helpless creatures.
As stated before, an unconscious character is helpless, but not all helpless characters are unconscious.
Some paralized creatures might be helpless. Some others might not. Charles xavier can levitate, probe your mind, and use psionic blasts while paralized, so getting the "paralized" condition does not mean he is "helpless". On the other hand, Wolverine would be helpless if paralized.
The rules say otherwise.
Nowhere they state that a paralized creatures is helpless, and even if they did, you cannot CdG a non-unconscious target.
Being paralized doesn't equate to being unconscious.
In 5e, where "helpless" is not a set condition that is hardcoded in the rules, but a description, the DM can easily say that the hostage is helpless, and thus, if the villain slits his throat, the hostage is coup-de-graced.
In other editions, he attacks him with the dagger, for regular damage, and depending on the edition, maybe a minus to attack (because they are both considered grappling)
So the DM can easily overcome any defense the PC could have simply stating that they are not grappled, they are helpless.
Brilliant.
No. But he can't be coupdegraced if he is executed.
If he is executed he was helpless. Cause -> effect.
By stating that someone is helpless only to make him executed is postponing the cause after the desired effect.
In fact, with rules as these the PCs can never know before what could make them helpless, and what risks they could take.
Quite annoying and uninteresting.
In the same way, when someone grappling someone else tries to stab him, that's not a coup de grace, but when someone is holding a hostage with a dagger in his neck, it is
How, ruleswise, can you declare that you are holding your foe hostage with a dagger in his neck?
What checks/actions should you use?
Mattachine said:
The DM gets to use common sense to decide on helpless.
Let's try some common sense.
Would you declare a paralized creature helpless?