CORE MECHANIC
I developed this mechanic to be able to be calculated on the go without reference to charts or books.
So here it is.
If your character is Proficient in a Save or Skill you add ½ level rounded up.
If you are not Proficient, you add ⅓ level rounded down.
If you are a Master at the Skill you add your full level.
Example of Mastery: Rogues and stealth…Wizards and Arcana, most background abilities, Bards and music.
Adjust all difficulty classes to the below on the fly.
VERY EASY DC 5
EASY DC 8
MEDIUM DC 10
TRICKY DC 13
HARD DC 15
VERY HARD DC 20
BRUTAL DC 25
NEAR IMPOSSIBLE DC 30
CORE MECHANIC CHART.
Level Prof Not Prof MASTER
1 1 0 1
2 1 0 2
3 2 1 2
4 2 1 4
5 3 1 5
6 3 2 6
7 4 2 7
8 4 2 8
9 5 3 9
10 5 3 10
11 6 3 11
12 6 4 12
13 7 4 13
14 7 4 14
15 8 5 15
So why is this System any better…? Well, the only real difference is that it's easier for the DM to calculate on the fly for monsters or NPCS…you don't NEED to open a book and look at a chart.
It is very close to all the other Core mechanics of 5e and 3.5 etc.
If you are interested in the comparison here is the maths.
Spell save comparison.
For a spell at 1st level Burning hands…
In WTHB - Spell save DC = 8 + 1/2 your level rounded up + your Intelligence modifier
1st level Wizard with 16 int cast a burning hands at a 1st level fighter with 14 dex and a 1st level rogue with 16 dex.
The DC is going to be 12. The Fighters save is going to be +2 and the Rogues will be + 4 The fighter will have a 55 % chance of making the save. The rogue will have a 65 % Chance.
Compare to 3.5
DC is 10 + spell level + Int mod.
DC will be 14.
Fighters save will be +2 Rogues save will be +5
The fighter will have a 45 % chance of making the save and the rogue will have a 60 % chance.
Compare to 5E.
DC will be 13
Fighters save will be +2 rogues will be +5
The fighter will have a 50% chance of making the save and the rouge will have a 65% chance.
New Scenario…
6th level wizard with 16 int casts lightning bolt at a 6th level fighter with 14 dex and a 6th level rogue with 16 dex.
The DC is going to be 14. The Fighters save is going to be +4 and the Rogues will be + 6
The fighter will have a 55 % chance of making the save. The rogue will have a 65 % Chance.
Compare to 3.5
DC is 10 + spell level + Int mod.
DC will be 16.
Fighters save will be +4 Rogues save will be +7
The fighter will have a 45 % chance of making the save and the rouge will have a 60 % chance.
Compare to 5E.
DC will be 14
Fighters save will be +2 rogues will be +6
The fighter will have a 45% chance of making the save and the rouge will have a 65% chance.
New Scenario
In WTHB
10th level wizard casts… Cone of Cold…lt at a 10th level fighter with 14 dex and a 10th level rouge with 16 dex.
The DC is going to be 16. The Fighters save is going to be +5 and the Rogues will be + 8 The fighter will have a 50 % chance of making the save. The rogue will have a 65 % Chance.
Compare to 3.5
DC is 10 + spell level + Int mod.
DC will be 18.
Fighters save will be +5 Rogues save will be +10
The fighter will have a 40 % chance of making the save and the rogue will have a 65 % chance.
Compared to 5E.
DC will be 15
Fighters save will be +2 rogues will be +7
The fighter will have a 40% chance of making the save and the rogue will have a 65% chance.
So the Final data for the 1st level at least is …
System Spell Fighter Rogue
WTHB Burning Hands 55% 65%
3.5 Burning Hands 45% 60%
5e Burning Hands 50% 65%
WTHB Lightning Bolt. 55% 65%
3.5 Lightning Bolt. 45% 60%
5e Lightning Bolt 45% 65%
WTHB Cone of Cold 50% 65%
3.5 Cone of Cold 40% 65%
5e Cone of Cold 40% 65%