Sorry for the delay. Here goes:
In RMC, we played an introductory campaign for 3 players. I used the adventure seed mentioned for the town of Merund in the Bay of Izar section of the Master Atlas 4ed.
The party was returning from a trip and an NPC had suggeted they go through Merund, and mentioned they were producting great works of art. Another NPC mentioned she was taking a bunch of kids for a field trip up to the same town, so she asked the party to escort them.
Once there they learned that most of the kids and adults were pursing their artistic drives, and most were going abroad to hone their skills, leaving the town without most basic needs.
Rita was an elven xylophonist, who was staying at the place which used to be the inn, but had been turned into a music school. They invited the party to stay the night.
In truth Rita was a lvl 5 bard, working for the Sirens of Sorak and trying to undo the town like any good unlife fellow would do. I think they wanted to remove the town to avoid suspicion for some activity they wanted to pursue in that region.
She was using suggestion bardic spells to give and mantain these ideas that the townsfolk should attempt to try pursing artistic dreams.
She cast a demonic possession for some rounds on a poor child in the music school, to then announce that the cure for such a thing was in the swamp to the north. This swamp had corpse candles and her idea was to get rid of the party, who obviously took the bait and tried to "get the antidote from the deepest part of the swamp".
She sent some goons to make sure they reached their destination, so when the party survived the lure of the candles they attacked and captured the party. The enemies here were lvl 3 warrior monks.
While being imprisoned they listened to their captors and learned that Rita was involved all along. They had been taked to an old tower, where seemingly old men were guarding them. They could find some excavation plans since the Sirens of Zorak were searching for old Kaeden jars in the mountains of the region.
I think there were some prisioners, who ended up being people from the town who had "gone away to pursue their artistic dreams".
The party escaped and defeated Frennya, a lvl 2 bard (with a x2 pp for bards, AT 7 +10, some ranks in Mind Domination and Mind Erosion), and her guardian, a lvl 2 rogue.
They went back to warn others of what they have learned, and eventually are put in contact with Vurkanan Tyes the Loremaster, who was investigating the region. I intended they to detour while helping him investigate some not completely related stuff, but I had to cut the campaign short.
I prepared a last adventure where they investigate some unusual activities in the mountains near where they were, and found Rita and the goons who had defeated them the first time. And they were accompanied by a freed Kaeden. So the final combat was difficult for them, but they got out of it alive, and defeated all the members of the Sirens of Zorak in the region (that they knew of), and stopped them from digging out Kaeden jars.
So the last battle was against 2 lvl 4 warrior monks (they leveled up from the last encounter and had some +5 items for combat), 1 lvl 5 bard (who also knew Mind Death, Mind Disease and Mind Domination to lvl 10, had the Charismatic and Quick Thinker backgrounds, a x2 PP and a Daily II with Blur).
All of these took 2 character design sessions (2 complete Rolemaster newbies and 1 experienced player), and 11 sessions of some 4-6 hours each.
Another time the Sirens of Sorak appeared was on a mini RMU campaign I prepared to test ERA with the new rules. The party was tasked by the Loremasters to lay low (they were refugees of some kind) while helping investigate activities in a small town.
They went about searching for clues and encountered several shadow creatures: first a shadow with the shape of a boar attacked in the forest, then a shadow shaped eagle. All the while learning about some mystical mirror that used to be owned by a famous Illusionist from Zinvar (before it got wiped out).
The Loremasters arranged passage for them to Zinvar, where they found the old house of the family and inside it the very old but still (undead) body of a trapped member of the Sirens of Zorak, along with the bones of her guardian.
The story was that the Illusionist had found a K'ta'viiri mirror that allowed summoning energy from the Plane of Light, but the Sirens were also tracking it for their purposes. The Illusionist got the mirror and trapped the Siren and her guardian, but after Zinvar got destroyed the wards keeping the Siren prisioner went out, and she had turned herself into an undead although still trapped and was able to start using the mirror with the knowledge she had gained while tracking it originally.
The party was not able to open the prison of the undead Siren, but they removed the mirror from the Illusionist house until it got out of her range, and handed it over to the Loremasters.
I don't have any stats for the Siren or the Guardian in this case, since the Guardian was long dead (I described the bones lying around inside the prison), and the Siren operated through her manipulation of the energies of the Mirror, which ended up being represented as the stats of whatever creatured she summoned through it. The power of the Mirror allowed her to control a form she knew of, it was easier if it was something that ocurred naturally there, like the board in the forest or the eagle in the hills, for the last battle she conjured shadows of flying demons, but she was nearer the summoned destination and I wanted a more climatic final battle.
This was all done with 1 character creation session and 7 adventure sessions of about 4-6 hours, played by 1 newbie and 4 experienced players, who had all previously participated in several simulated RMU scenarios to understand the new rules.
Well, that was a trip down memory lane.
Let me know if there is something else I can tell you from these campaigns.
