The Sun is the star at the center of the Solar System.
Felt by Lily
Having fallen in love with someone long ago and had children with them, Lily would enjoy laying in the Sun with them and feeling the warmth. However, Lily later became a demon, and found that she could no longer experience the feeling, upsetting her. Lily began to rely on her memory of the sun, finding it to be a more pleasant memory to think about than the loss of her children.
S.H.I.E.L.D. operated a program known as Slingshot, in which dangerous objects were launched into the sun to be destroyed. One such launch occurred in 2013 and was watched by Coulson's Team. However, the rockets were empty, as the objects were in fact in the Fridge. S.H.I.E.L.D. occasionally sent a monkey in the rockets for fun.
Erik Killmonger's Demise
Following a final battle between T'Challa and Erik Killmonger, Killmonger was defeated and left mortally wounded by T'Challa. With little time left for him, Killmonger was taken to the Great Mound by T'Challa to watch the sunset in Wakanda, which he had been told by his father were the most beautiful in the world, with Killmonger noting the beauty of this sight. Killmonger had watched the sunset as he died, choosing to die rather than live as T'Challa's prisoner.
As part of K'un-Lun's ceremony to find who would win the title of Iron Fist, the final challengers were determined to be Danny Rand and Davos, who engaged in a final duel to determine the winner. Throughout the duel the pair were equally matched, resulting in a long duel, although Davos began to gain the advantage. As the sun rose, Rand decided to use this to his advantage, leading Davos into the path of the sunlight, which had then momentarily blinded him, allowing Rand to defeat him and Lei Kung to declare Rand as the victor, much to the dismay of Davos.
In 2018, S.H.I.E.L.D. had made a plan to destroy the Gravitonium by launching it directly into the Sun before he could be used once again by HYDRA, as they intended to use Zephyr One to slingshot it out of their atmosphere. However, as the Gravitonium had been absorbed into Glenn Talbot's body, causing him to gain super powers and then go on a rampage, Quake was forced to battle Talbot, resulting in her using her enhanced power from the Centipede Serum to launch him into space, where Talbot's body then floated into the sun, which had finally killed Talbot and destroyed all the remaining Gravitonium.
Ikaris attempted to stop his fellow Eternals from preventing Tiamut the Communicator's Emergence, which would have destroyed Earth. However, Ikaris and Sprite failed, eventually choosing to join the Uni-Mind. Distraught over having betrayed his creator, Arishem the Judge, Ikaris chose to kill himself by flying into the Sun. He approached the Sun and closed his eyes as he got consumed by the flames, dying.
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