I have been thinking about an idea for what I call a stepped dice combat system. Each class and creature has a particular die type that they roll for combat. Higher level characters and more powerful monsters have bigger dice.

Some examples:

Fighter d8

Rogue d6

Mage d4

Goblin d4

Orc d6

Troll d12

Dragon d30

For combat, each combatant rolls their die. Higher die wins and the loser gets hit. In the case of a tie, both combatants take damage. I am also thinking if the loser has a shield that in the case of a tie, he can chose to block with the shield and the shield takes damage.

Combat example:

1st level fighter encounters a goblin. The goblin rushes up to attack:

Fighter rolls a d8 and gets a 6

Goblin rolls a d6 and gets a 4

Fighter wins combat so he rolls a d8 for his longsword and gets a 4 for damage

Goblin rolls a d6 for armor 1-2 = 0 points absorbed 3-4 =1 point and 5-6 = 2 points. He rolls a 4 and blocks 1 point of damage

Goblin has 4 hit points and takes 3 damage so he is still alive with 1 hit point.

The next round of combat begins.

I have multiple goals with this system. I want even a weaker character to have a chance, no matter how small to hit a more powerful character (even though thick armor means he may not be able to damage it.

I also want more powerful characters to easily hit weaker creatures. I have lots of permutations to the system I am thinking about, including allowing higher level fighters to hit multiple enemies in one round. I also am considering having 'steps' added to damage when one character has a much higher roll than the defender. For example, if a troll is fighting a goblin and the troll rolls an 11 and the goblin rolls a 2. Subtract 2 from 11 for a difference of 9. Each 'step' of damage is 4 points so 11/2 = 9 and 9/8 = 2 rounded down so the troll rolls gets +2 to his damage roll.

Of course there are lots of permutations to the system, like how to handle ranged combat, etc.

So, what do you think? Is this a terrible idea? Did I unintentionally rip-off of another system? If you like or dislike the system, please give feedback and tll me WHY! Thanks very much!