In the original campaign, before players created a character, they would have to roll on a small table. This table was modified by the character's race. The result of this roll determined whether the character was considered one of the Empty, one of the Unblessed, or one of the Blessed. The idea was that all magic in whatever form, came ultimately from the gods, and it was they who decided whether or not a person would ever be able to use magic.
I'm not sure how to apply the following within Rolemaster terms, so ideas and comments are certainly welcome.
A character could be "Blessed." Blessed characters have an innate understanding of magic, and are able to use small amounts in every day life. In d20 terms, they were able to cast low-level spells from a random type (bard, cleric, druid or sorceror) a few times a day. The Blessed usually went on to become full spellcasters. They chose a small number of spells they knew (everything was based on Cha bonus). Further, everyone who fell into the category of 'Blessed' tended to have some undefinable attractiveness about them, a touch of the fey, as it were.
The "Unblessed" were simply those who showed no unusual aptitude for magic. They could train as a spellcaster, but would not have the bonus spell capability of the "Blessed." These were the ordinary, every day folk, who may or may not go on to become wizards and sorcerors.
The "Empty" were on the opposite side of the scale from the "Blessed." For some reason, they could never learn magic, and magic never seemed to work on them. Now this one is pretty easy to figure out: I imagine that magic skills would always be restricted for these characters, and they would get a sizable RR modifier.
And then there was a special category, reserved for use as monsters, called the "Ravenous." Not only were these creatures immune to magic, like the Empty, but they also were healed by magic. No matter the intended effect of the spell, they would regain hit points instead of suffering the normal effect. Further, they had a touch attack that could drain magic items, and deal temporary damage to spellcasters. They were sort of like vampires in that they had to drain magic on a regular basis to survive.
So I'm open to ideas here. Any suggestions?