This was inspired by a previous question where the poster had mistaken what hit dice were for, thinking you could use them for a damage bonus. Which made me think…what if there was a class where you could use your hit dice for other things?
Hence the Implacable Warrior.
Design note: Hit dice are a scale-able resource but they don’t regenerate in their entirety after a long rest. And with few at lower levels this may cause players to hesitate to use them. Hence this class also has ‘determination dice’ which go into the same ‘pool’ as your hit dice and act as a buffer, encouraging their use (especially as you get all determination dice back after a long rest).
Your sheer determination powers you on against the odds. You are able to push on when others would fall by virtue of your iron will.
At 3rd level you gain proficiency in Wisdom saving throws
You also gain two determination dice. These dice are d10s. At 10th level and 15th level you gain an additional determination die (for a total of 3 at 15th level).
Whenever you spend a hit die, either to regain hit points after a short rest or for any of the features of this subclass, you may spend a determination die instead. You regain all determination dice after a long rest.
At 3rd level, whenever you successfully hit a creature with a weapon attack, but no more than once per turn, you may spend a hit die. If you do so, roll the hit die and add the result to your damage roll.
At 7th level, whenever you use your Second Wind feature you may spend a hit die. If you do so you also gain temporary hit points equal to the result of the hit die + half your fighter level.
At 10th level, if a creature within your weapon range casts a spell that forces you to make a saving throw or successfully hits you with an attack roll you may use your reaction to spend a hit die.
If you do so, you immediately make a weapon attack against that creature. If the attack hits you may then either add the result of your hit die to the result of your saving throw or subtract the (result of your hit die + your fighter level) from the damage taken.
At 15th level you refuse to lay down and die. When you are reduced to 0 hit points but not killed outright, you can use your reaction to spend a hit die. If you do so you drop to 1 hit point instead and gain a number of temporary hit points equal to the the result rolled + half your fighter level. However, your maximum hit points is also decreased by the result of your determination die.
Your maximum hit points are restored after completing a long rest.
At 18th level you have reached the epitome of the unstoppable warrior. Whenever you use any of the features of the subclass that allow you to spend a hit die, you may spend two hit dice instead (rolling both and using the total).