“I want to aim for his eye! So I can blind him, and kill him in one shot!”

“Okay, his eyes widen as he sees your malicious intent, and he throws up a guard. Make an attack roll.”

“What modifiers for aiming for his eyes?!”

“None. You’re always aiming for your foes’ eyes.”

“No I’m not! I’m just trying to hit. I want to do a lethal blow now!”

“You’re always trying to land a lethal blow, unless you do something special not to. It’s a fight. Your character is always doing their best unless you say otherwise. Your attack rolls already represent the very best attack your character thinks can land. Of course you want to stab him in the eye, or cut off his head, or pierce his heart. And that’s represented by the existing combat rules of the game. And when the foe goes down, that is when you succeeded.”

“But maybe I can do those things before that!”

“Sure. It’s called a “critical hit.” in this game. A “stunt” or special maneuver in other games.”

“But I want a SPECIAL chance to kill him in one shot!”

“Okay. Do you want every foe you ever fight to have a special chance to kill you in one shot, too?”

“You’re no fun!”

“If you want to try to be flamboyant in your attacks because that’s fun, I am fine with that. That’s why I said he reacted to your effort. And if this attack kills him, it’ll be because you ran him through the eye, and that’ll be awesome.

If you want to have a reduced chance to be effective because of what you are trying, feel free to not use your full combat bonuses.

If you want an increased chance to be effective because of what you are trying, once I allow that why wouldn’t you always do that? And every other PC? And every NPC?”