I was looking at the modifier types in the homebrew "create modifier" page and noticed that in the bonus modifier subtypes list there are subtypes like half proficiency, proficiency bonus and twice proficiency bonus; when I scrolled over other modifier types I saw proficiency, half proficiency, twice proficiency and expertise.
What is the difference between bonus proficiency and proficiency? Also what is the difference between twice proficiency and expertise.
Some class abilities will give you expertise such as the rogue feature;
Expertise
At 1st level, choose two of your skill proficiencies, or one of your skill proficiencies and your proficiency with thieves’ tools. Your proficiency bonus is doubled for any ability check you make that uses either of the chosen proficiencies.
Whereas others will say you get to double your proficiency bonus on rolls with certain skills, such as the Knowledge domain Cleric;
Blessings of Knowledge
You also become proficient in your choice of two of the following skills: Arcana, History, Nature, or Religion. Your proficiency bonus is doubled for any ability check you make that uses either of those skills.
The simple truth that there is no difference between the two features functionally, they both give you double your proficiency bonus. It comes down to some truly awful butchering of the English language by an American company.
Half proficiency just means that you get to add half your proficiency bonus to a skill as long as you don’t already get either your full or double proficiency bonus. An example of this is the Bard jack of all trades feature;
Jack of All Trades
Starting at 2nd level, you can add half your proficiency bonus, rounded down, to any ability check you make that doesn’t already include your proficiency bonus.
So "proficiency" grants proficiency, while "bonus proficiency" increases it i.e. you can't have bonus proficiency unless you initially have proficiency; is this correct?
What about "bonus twice proficiency: If expertise doubles an initial proficiency and twice proficiency grants it, what does bonus twice proficiency do?
Proficiency: the state of being proficiency in something or not
Proficiency Bonus: the bonus value you add to any ability check, saving throw, or attack roll you make that you have proficiency in
Expertise: The ability to double your proficiency bonus in a skill you're already proficient in (think of it as proficiency bonus x2). Can only apply to skills you're already proficient in.
Twice Proficiency: Granting proficiency in a skill and that bonus is doubled (think of it as + (proficiency bonus x 2)). Can only apply to skills you're not already proficient in.
Bonus Twice Proficiency vs Twice Proficiency: System modifiers that were likely set up in the backend to do similar but different things. They have no rules distinction, it's just how the system was set up.
I was looking at the modifier types in the homebrew "create modifier" page and noticed that in the bonus modifier subtypes list there are subtypes like half proficiency, proficiency bonus and twice proficiency bonus; when I scrolled over other modifier types I saw proficiency, half proficiency, twice proficiency and expertise.
What is the difference between bonus proficiency and proficiency? Also what is the difference between twice proficiency and expertise.
Some class abilities will give you expertise such as the rogue feature;
Expertise
At 1st level, choose two of your skill proficiencies, or one of your skill proficiencies and your proficiency with thieves’ tools. Your proficiency bonus is doubled for any ability check you make that uses either of the chosen proficiencies.
Whereas others will say you get to double your proficiency bonus on rolls with certain skills, such as the Knowledge domain Cleric;
Blessings of Knowledge
You also become proficient in your choice of two of the following skills: Arcana, History, Nature, or Religion. Your proficiency bonus is doubled for any ability check you make that uses either of those skills.
The simple truth that there is no difference between the two features functionally, they both give you double your proficiency bonus. It comes down to some truly awful butchering of the English language by an American company.
Half proficiency just means that you get to add half your proficiency bonus to a skill as long as you don’t already get either your full or double proficiency bonus. An example of this is the Bard jack of all trades feature;
Jack of All Trades
Starting at 2nd level, you can add half your proficiency bonus, rounded down, to any ability check you make that doesn’t already include your proficiency bonus.
Bonus->Proficiency increases your Proficiency Bonus, Proficiency->X grants that Proficiency.
Proficiency let’s you add your Proficiency Bonus to an Ability Check or Saving Throw. Expertise lets you choose a Skill or Tool you are already proficient with and doubles your Proficiency Bonus for that selection. Twice proficiency grants proficiency in a skill or tool and doubles it. I explained it in more depth here: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/rules-game-mechanics/92413-whats-the-difference-between-expertise-and-double).
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So "proficiency" grants proficiency, while "bonus proficiency" increases it i.e. you can't have bonus proficiency unless you initially have proficiency; is this correct?
What about "bonus twice proficiency: If expertise doubles an initial proficiency and twice proficiency grants it, what does bonus twice proficiency do?
Proficiency: the state of being proficiency in something or not
Proficiency Bonus: the bonus value you add to any ability check, saving throw, or attack roll you make that you have proficiency in
Expertise: The ability to double your proficiency bonus in a skill you're already proficient in (think of it as proficiency bonus x2). Can only apply to skills you're already proficient in.
Twice Proficiency: Granting proficiency in a skill and that bonus is doubled (think of it as + (proficiency bonus x 2)). Can only apply to skills you're not already proficient in.
Bonus Twice Proficiency vs Twice Proficiency: System modifiers that were likely set up in the backend to do similar but different things. They have no rules distinction, it's just how the system was set up.
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