Push Die!

Sometimes you want your PC heroes (and knaves) to push on, to try harder. Here's a game mechanic for any system where you roll high. The Push Die.

The Push Die is a die added to your normal resolution check to improve your odds of success. It is voluntary on part of the player if they will or will not add the push die to the roll and must be declared before making the normal roll to resolve a task. The push die should be rolled simultaneously with the resolution die, it's score being added to roll.

If the roll of a push die is a 1 the character suffers a point of fatigue. Tally that up and if fatigue is ever higher than 1/2 of the ability score related to an action the PC is now -2 to attempt that action (or at disadvantage if you use that mechanic in your game).

A HitDie of Fatigue is removed each full turn of rest a character takes. Magical healing will remove 1/2 of fatigue if the character is fully healed by healing magic. A DM may wish to add additional spells, salves, or potions t0 the game that remove (or inflict fatigue). A normal amount of full rest (for the night or a full rest break) this fatigue is fully removed.

If the resolution roll fails the full score of the push die is suffered as fatigue.

If the resolution roll fails with a fumble (a roll of 1 if you are using 1d20) the full score of the push die is suffered as fatigue and the related ability score suffers a point of strain. If the highest number was rolled on a push die than 1/2 that score is suffered as strain. Strain can be added up against each ability score. If strain is greater than 1/2 the ability score the character is now -2 to attempt actions with that ability. if strain exceeds a character's ability score they are overcome and unable to purposefully take actions that would use that ability and are -10 if forced to make a saving throw or reaction using that ability score.  Yeah -10, being virtually helpless should be a big deal.

An hour of rest will remove 1 point of strain in 1 ability score. 

I recommend a 1d4 be the base Push Die for all characters. If the ability score is a Prime Ability shift up a die. If the character has a score of 15 or more in an ability shift up a die.  A player may choose to roll less than their full push die if desired. So a Fighter with a score of 17 in Strength (a prime attribute in many systems) could roll 1d8 when pushing it. (or choose to roll 1d4, or 1d6 instead).

Why I like this mechanic.   There's no direct penalty for trying harder. But there is a consequence for trying harder and failing. The more players push it the more they will win...until they don't. I can also use a fatigue mechanic without having to always apply a fatigue score to a host of actions. Trying harder can cause fatigue but there isn't a constant penalty for action itself. Players that have their characters push on and on without resting will suffer more. those that do not risk will not reap rewards as easily however.