I can't find anything in the rule books that speaks to this specific question, so I figured I would bring it to the internet for a solid answer. I have a player that has taken the ability to tattoo "magic items" onto your body. During that conversation he mentioned that he crafted a tattoo for the ring slot that had about three or four different effects at one time. I wanted to check to see if this was a legal move? Can a ring carry more than one effect short of being an artifact? If it is one effect on a ring only, is this then ruled differently for the magical tattoo's?
You can have any number of abilities on any magical item. It just costs more.
Multiple Different Abilities: Abilities such as an attack roll bonus or saving throw bonus and a spell-like function are not similar, and their values are simply added together to determine the cost. For items that take up a space on a character's body, each additional power not only has no discount but instead has a 50% increase in price.
Thanks for the quick answer! I don't normally run high level games, so this is the first time I have actually had to deal with this and I was not feeling to confident about it. :)
In addition, this would be a custom item so it requires GM approval before it can be made.
If this player hasn't checked it out with you (as the GM) and is trying anything even slightly dodgy, simply ban all custom items.
At high level, particularly if you aren't used to running such a game, custom items can be very unbalanced. Even experienced GMs often ban them just to make their lives slightly easier.
Yeah, this is a custom item subject to your approval as a GM. All item creation rules are merely guidelines. You would not be out of your bounds to step in and say that he can only place one ring effect into the ring slot through the use of a magical tattoo.