You stated Juggernaut has never died when he in fact has and he confirmed so himself in a Spiderman issue which makes you wrong. Regardless of who killed him he HAS been killed, and no, Eternity cast him to Oblivion's realm where he grew old and died. Who has killed Hulk?
Completely forgot about Loebs shower of shit run on Rulk. What's funny is he jobbed out half of Marvel to make Rulk look good and now if anything, Rulk is jobbed more than anyone not named Thor.
In New Exaclibur when he was on the team. There was an arc involving him that tried to point out some of it.
It wasn't well written in terms of a retcon cause it didn't go into great details but it turns out that Xavier was Cyttorak's first choice and that somehow connects Onslaught to the gem or at least mentally drawn to it.
It's possible that somehow allowed him to bypass Cain's durability and draw the gem towards them.
cain hasn't been used in any capacity since his last appearance in dark avengers #183, when he ventured out to do his own thing with his 'juggernaut-power' fluctuating in and out.
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"I am tired of Earth. These people.
I am tired of being caught in the tangle of their lives."
He should of been harder to stop. If base Juggernaut is way stronger than Rogue then shouldn't this version who suppose have more power than before be much more powerful than her?