Link was overcome with pain, Dark's fist rammed into Links jaw. He kicked Dark in the stomach, Dark was filled with rage; Link lifted his foot up and smashed his head to the floor, he tried to grab his sword, but Dark grabbed his ankle through the tight grasp Link fell down, Dark got on top of him and starting punching his face, Link rolled on to Dark but when he went for the attack he rolled out of the way. Dark picked up the sword, the shock of Light made his palms bleed, but he started running away with it.

Link's hand stated glowing, the Triforce he had embedded in his hand was used as commutation appliance for guidances from Rheshu.
''Link, you need to catch Dark, if he holds that sword to long is may cloak the whole blade in darkness, he will calm as his own''
Rheshu could see the whole fight between the two identities she was stuck in a trance of awe. Hes skills reminded her of someone...
Link finally caught up with Dark and tackled him, Link stood up, kicked Dark in the leg, punched him and throw him over his shoulder. His sword slid across the room, Dark recovered from the fall.
Rheshu watched, her heart was racing but she suddenly was calmed down by the thoughts of her mind. She grabbed her sword and command into to transform to the guitar she loved to play on. She played a melody that was at the back her mind, she strummed the strings and the Trifroce was still on to Link.
''With darkness and silence through the night'' she sang.
Link paused through and put his hand up to his ear, he was stunned by the Rheshu's voice and was powered and it gave him a message to never give up hope.
''What a fear in my heart, you are so supreme''
Link dodged Darks attacks, and his mind was running with Rheshu's teachings, the teaching that The Boss and Big Boss TAUGHT her.
''In my time, Their be no one else!''
Rheshu sang this for Link, because it was encouraging him to never give up, she was guiding the path of Courage he always had. Big Boss never gave up, he was the bravest warrior of his time and this song is a memorable Honorable to guide those.

''I'm still in a dream SNAKE EATER!''

Link's widen his eyes, he flipped over Dark's head, He kicked the handle of the sword with his heel, it bounced up and with a flash he grabbed it and sliced off Dark's head.

---

''Find something to believe in, and believe in it for yourself. And when you do pass it on to the future''
-Solid Snake
Since Rheshu is so in touched with all the Dimensions she intends to pass down some stuff she learned. When Rheshu sang this she was think of Snake, I know this two are COMPLETELY separate games, but this is the point of Ruler of All Dimensions: teachings of the past, memories, and saving the ones you love. Since Rheshu was stuck in a trance she sang to Link as if he was Snake. Rheshu is learns, she passes the teachings down and she helps with other peoples lives.

Each Dimension has something like this, Rheshu remembers something that happened in the past and she brings it. She encouraged Link to never give up, just like how Snake didn't when times where his own life was hanging by a thread.
Wow, so Metal Gear Zelda IS a thing I thought I was the only one with an urge to connect the two.