Odin in the Destroyer armor was utterly shitstomped by the 4th Host. RKT might do a bit better than his father, but he ultimately gets pummeled in the end.
My point is, Odin had that enchantment all along, he just chose not to use it because of 'dire consequences'. We know this was BS because the Twins killed SCORES of Celestials with the Axe and Thor offed Exitar with it with ZERO 'dire consequences' apparent.
RKT was omniscient (or as close as you can get to it) he'd know of the enchantment his father created and use it to WTFstomp these clowns.
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..even the outer hells are indifferent matters for they bow only to potent and archaic Nodens.
You're acting like the Jarnbjorn enchantment was even a thought in the writers' heads back when Odin originally fought the Host. It obviously wasn't. That was just a plot-device Marvel came up with during the most recent Exitar fiasco... But that's neither here nor there.
I highly doubt that using Jarnbjorn is in the spirit of this thread, given that the OP doesn't mention it among Thor's options: "Rune King Thor can access the Destroyer armor and the Odinsword."
Sans ridiculous plot-devices, Thor gets stomped just like his daddy.
Yep, and RK Thor is well above Those that sit above. RK Thor obliterates them. There is absolutely nothing that the Celestials could do to him. RK Thor was written to hold all power over the metaphysical universe. Nothing in the physical universe had any effect on him, because things like pain, death, disease, fatigue, kayoed state, etc, hold no meaning to him. They can't kill him, or hurt him. I mean what are they going to throw at him that would affect him? The Celestial host are small fries compared to RK Thor (a true omniscient).
Loki found a loophole to defy the orders he was given,
so 'Those Who Sit Above in Shadow' gave Loki what he wanted, which was to rule the nine realms,
but they played Loki as Uatu appears and tells us,
they set Loki up at the end of time where the nine realms are heading towards entropy.