So I was wondering what people thought of the game balance issues of a magic item idea I'm directly stealing out out The Dresden Files :)

In those books, the main character has a magical ring which saps some of the kinetic energy of his everyday movements ( sort of like wearing wrist weights in its effects, I guess ), and stores it, allowing him to channel the stored kinetic energy into a blow later on.

That seems a very Monk item, to me.

I was thinking of structuring it so that every 10 landed open hand attacks ( or so ), the Monk Character could land bonus force damage - say +10 damage, or +d10. It is kind of like giving them a +1 to damage but piling up all the results onto one single strike - but not quite, as you could theoretically use attacks landed on opponent A to change up a "whammy" for opponent B.

How does that does that sound from a balance perspective? I'm open to changing up the number of "charges" required, or the amount of bonus damage done.

I'd like this to classify as a "major magic item".

Also - any idea how one might implement that under the home-brew system?  I can absolutely create a charged item, using any wand as a template, but the Character Sheet interface for changing the number of charges is inconvenient for a Player to be opening that up and tinkering with the number of charges every time they successfully land a blow. Ideally I'd like a nice little checkbox track I can put under their attack section, like they have for Ki, say, something like a code snippet in the open hand attack description ( although that doesn't work ).

Ideas? Both on balancing it, and incorporating it into the Character sheet?

Thanks,

 Edit: OK - it occurred to me that if the ring is absorbing kinetic energy from landed unarmed attacks, there's really nothing to prevent the Monk from beating the heck out of bag of sand during a rest period to recharge the ring. So, I'll have to make up some mumbo-jumbo about the energy being generated by the violent clash of the attacker and defender's Ki in the heat of combat, or some such, to make it only actual attack blows which can charge the ring.

Edit: I'd kind of like to make the damage scale by Character Level, keeping the item relevant, even as the monk levels up, but I don't want to overpower it. Say ... 8 + 1/3 Character level instead of 10 flat damage?

OK - so far as building this a homebrew, I can make this a custom magic weapon - but I can't make the base weapon type Unarmed Strike which is annoying.

I can make it based on Quarterstaff, which scales the same way as Unarmed Strike - except it has that annoying versatile property that Unarmed Strike does not. Ideally, I'd like to be able to remove versatile , but it's workable as is.

I can make it charged, and a I can attach a simple 1st level homebrew spell that does the 10 points of damage to simulate the discharge of the built up kinetic energy.

If you are  going to use a weapon to represent it, use a club.

Quote from DxJxC >>

If you are  going to use a weapon to represent it, use a club.

Perfect! Many thanks!

If you want it to scale by level, maybe it would be easier to say, rather than a base 1d10 extra damage plus level based modifier, just say that the player can add x number of extra unarmed damage die to the damage roll (since the unarmed strike damage already increases with the monk's level) 

adding damage dice makes it really powerful though, does it not? To keep it from getting too OP, I'd want to have it scale very slowly.

My current iteration is 8 + 1 additional point of damage per 2 Character levels. 

At the Character's current level of 5, that makes for +10 to damage, every 10 hits, for an average of +1( but as noted, not quite the same as +1 as it all piles up on one strike, and possibly multiple combats pile up on one opponent ). At level 20, that would make for +18 every 10 hits, for an average of +2 (1.8).

It's kind of weird from a balance perspective, I admit.

If you made it, say, two additional damage die, then at 5th level (1d6) , they would average an additional 7 damage per 10 hits, and at 20th level (1d10) they would average an additional  11 points of damage per 10 hits. (assuming I am doing my math right). 

That might be a bit low. With 3 additional damage die, at 5th level it would be an additional 11 points of damage on average (10.5) and at 20th level an additional 17 points of damage (16.5). 

Which, I would say is pretty close to what you are quoting right now with your method, but without the need to do anything extra with dividing out the character level.  

Pretty elegant! Thanks :)