I'm working on a pen-and-paper RPG, and I'm trying to consider a more unique approach to determining the accuracy of attacks. I wanted to make this a very simple process that doesn't impose any math on the players. e.g., roll a single die, and check the value to determine whether an attack is effective or not.

What I don't like about how D&D handles this (at least, older editions) is that the player was tasked with checking a look-up table, depending on the enemy's armor class. I don't want to impose anything like this. It needs to be far more simplified.

The basic idea here is that any armored character or creature can absorb most any blow that's directed at it. Presumably, wearing armor means that your armor is going to stop a weapon dead in its tracks, thus making you much more difficult to successfully damage. The game must determine when an attack either hits a vulnerable, non-armored area of the target, or otherwise pierces the target's defenses somehow. So, this to-hit system need only consider the armor class of what is being targeted, and not the attacker's own accuracy or type of weapon being used. The finer details are left to abstraction.

What I was thinking was requiring the attacker to roll a single die and aim for a value that's greater or equal to the target's armor class. There are some issues, though: Which die represents a balanced probability that can universally encompass all kinds of attacks; what if the target's armor class is higher than the maximum value of the die? As far as the latter is concerned, I think there can also be a bonus on an attacker's to-hit score, which means this value is added to the total value that was rolled. If, for instance, you had a to-hit bonus of +2 and you rolled an 8, the outcome would be considered 10 instead. (8 + 2) In cases where a target has some abnormally high armor class, you might only be able to hit it if you had an adequate to-hit bonus to match. I'm really not sure how this looks in terms of overall balance, though.

Any insights would be appreciated.

Making up rules is my favorite part of designing a game, actually. I just don't have much experience in the department of pen-and-paper games, where there's a greater need for balance. With video games, you can make the whole rule system more of a commodity than a serious attempt at balance.

That, and the whole pen-and-paper community is far more fickle about these details. If you put a +1 bonus in some area it doesn't belong, you can be sure the entire system will be accused of being broken.