Orcs that didn't pillage? He had them brought in. A spell to see into them provoked what could only be a counter-spell.
Their camouflage dropped easy. The man's mind was like an open book. Beren, on a mission to steal Melkor's jewels, at king Thingol's bidding, as a bride price for wedding with Luthien.
Elves... were always more difficult. He succeeded with most of them. Those who resisted, did so at great cost to their functioning. While shielding themselves from Mairon's words, they couldn't physically block a pillow tossed at them.
Except that one.
He was calmly singing.
He didn't lose balance, didn't seize his head...
...slowly walked forward, sword in left hand, dagger in right.
/ How many left-handed elves do I know? /
Mairon focused on him, relaxing hold of others, and for good measure, picked up mace. This elf had cast the spell of concealment, and could do more.
"You weren't very good at acting orcish. Slashing and burning is a fond cultural tradition, you know. Mushrooms and berries they consume in deadly peril. Rodent, bird and snake would be considered appropriate healthy snacks."
"True enough. Then again, maybe our camouflage wasn't meant to endure. No walls did we climb, no battles we fought, yet here we are."
"Do you imagine that an advantage?"
"Currently I do, for this is Tol Sirion... how come you haven't built your own fastness? You can build - I know you of old times. Without asking have you settled here. This is not your island, not your river, not your place."
"I have made it mine. Unless you name yourself and claim it from me."
"Findaráto Ingoldo, you would know me as, but recently they call me Finrod Felagund. I helped create this island, designed this fort and both bridges. This place trusted my judgement for a long while. Listen to advise, withdraw. Let us pass."
"To the halls of Mandos you may pass unhindered. Elsewhere do not hurry."
"To pass elsewhere I intend however. The act of taking didn't make this yours."
A tremor ran through ground. Felagund sang on, reaching out to the island and the river around it. He reminded them of their beginning, of Aulë and Ulmo, of elves who had asked for aid, of their careful shaping, of words said to make them endure, promises given, good times seen. He reminded of their original purpose.
Mirroring a battle of more ancient music, Mairon tried to intervene in the spells, alter their meaning, find moments of ambiguity and usurp the elf's bond with the place.
Felagund however made no mistake. He seemed to know exactly what he must and may not. Against an opponent of greater stature and skill, adventurous moves would bring him down. He did not make any. He sang of things he knew, appealed for aid of forces that were loyal. He sang of holding course in darkness, building trust, overcoming hardship, growing slowly.
Mairon tried contending with the song, but truth be told... he was not good at music. For one whose spirit also sang in the creation, that was somewhat embarrassing. Mairon worked in more reliable, repeatable arts. The fact that Felagund's spells were song, was an impediment for him. Creation itself had been done the wrong way, it had left him confused and dissatisfied.
But here, time was running short. He swung the mace and multiplied the weapon's power with words. Felagund jumped directly at him, but didn't attempt to land a strike. Instead the elf dove past him. Mace missed their mark and hit the wall of the tower, causing it to explode outward while floor collapsed underneath.
/ Oh well, a few bumps and scratches. /
Shaking off stones, Mairon saw that the elf-king had landed on feet.
/ Bloody sprites, jumping onto a flying rock. /
Some of his companions were knocked out though, others bruised. Felagund stood facing outward towards the broken tower, in the middle of the courtyard. Who remained standing of his company, had armed themselves around him.
"I'm failing you, comrades.
I cannot protect you for more than a few minutes.
Forgive me, this is going like I hoped it would not go."
None of them wavered, though some despaired. Wolves and orcs were hesitant - the first to move would meet certain death. Earth was shaking and water had become incredibly violent. Wind and waves flung intense gusts of spray over the outer walls. The bridge was hardly visible among their rising crests. Also, there was a pattern in the water which Mairon clearly saw now.
"I notice you intend to flush yourself halfway to Valinor."
"All of us, all the way... unless you make a reasonable choice and back down.
I cannot defeat you in combat, but I am asking the island to undo itself.
If I ask once more, I think it will oblige. Collect your servants, go and build your own place."
"Oh, I could... but why let someone burglarize my master? Why not embrance our mutual destruction, and escape as a spirit, as you know I can."
The elf might bring down everything, but not escape.
"You note correctly, one whom I guide has sworn to take a Silmaril from Morgoth. If you asked me, I would note that Morgoth didn't make the Silmarils. Robbery begets burglary, violence begets war... I didn't start it, you didn't either. Morgoth did. Rain can't complain about wet.
I don't know what he promised you, but take note of what you have received. As for escaping, scornfully would he mock thy naked spirit if you returned to him. Myself would Mandos accept with compassion and respect. If I went there, I might even meet whom I love."
Mairon knew... Felagund was not bothering with deceit. His words were true and precise, and that left more than a scratch. Mairon had grown used to constant manipulation and having to wring out truth.
"Apparently you have convinced me, cave-maker. I need to compromise.
I will heed your advise and build my fort on the other shore.
Do not think however that you are free to pass my gates there."
"I don't expect to be trying that... oh, and thank you for your sensible choice. I miss the one who was called Mairon, when times were different."
That was something he didn't expect. Losing a turf to its maker was foreseeable. Being thanked was not.
He waved a command. Wolves ran and orcs marched quick. He walked last and made it sure that in his footsteps, the bridge cracked and crumbled into the river. The distant song of Finrod Felagund faded and the river calmed.
He sent a vampire to deliver word to Melkor, and immediately started work.
The new fort would be his own.