i still think that Cain Marko who hates his brother starts beating charles, this is the point where charles first gets his powers, Charles does something to Cain that totaly disrupts his mind.... bringing up his greatest fears, making him go crazy untill he falls unconcious.... since charles has only just developed his powers that second, his body and mind wasnt use to that much of a change and with that big of a mental outburst something happens to his spine that makes him crippled....
Cain is in some sort of secret mental facility the goverment runs, cain is there healing from the incedent, the goverment volunteers cain as a mutant killing experiment they give him ultimate strength and invulnerability.... as he awakens he is pissed, he goes on a rampage throughout the facility (a experiment gone wrong) nothing in there can stop him, he escapes with one thought in mind, to kill charles...
knowing his brother is a telepathic mutant cain knows he cant do anything without being protected from psychic abilities, he comes across magneto and asks for his help, magneto creates a helmet, much like his owne that enables psychic powers from affecting him, cain becomes the juggernaut...
Juggernaut is in a battle with the x-men (at the time Cyclops Jean and Storm) they stand no chance against him he is tossing them around and it seems like theres no chance when he grabs cyclops and about to kill him jean outbursts in power, you see a minor scale of what the phoenix can do as she blasts juggernaut back with basicly everything shes tossing at him with telekenesis some how it shows her stopping the Juggernaut in his tracks and sends him flying into an ocean or something, all the x-men are unconcious coinsedentaly so they didnt see the power from jean.... she collapses from the power and falls unconcious, You see a glimpse of xavier at the mansion and a feared look on his face...
^those would be flashback scenes of juggernaut^
Opening scene, Juggernaut is rampaging through a city the same city that the worthington mansion is in, Angel contacts the Xavier (his old friend) for help to stop juggernaut (you dont get a good glimpse of angel so you dont really know its him) Xavier refers to him as Warren on the phone...the x-men are sent out to stop him (Wolverine storm cyclops and iceman (newly added)) they split up trying to find him through the city, you get to see team work in the works... Cyclops seees juggernaut and juggernaut atacks him (like the story board) then while cyclops is on the ground juggernaut runs for him again but cyclops is saved be some person with angelic wings, you only get a back view.... now the audience is in there feet, who is this guy with wings?.... now wolverine jumps for Juggernaut andcovers juggs eyes with his hands, Juggernaut tries shaking him off while he stomps around, Iceman freezes the ground below him and juggernaut slipps and falls on his bottum as the earth shakesand buildings start to crumble.... wolverine jumps off and you see storm wolverine and Iceman standing beside each other then angel lands beside them with cyclops in his arms... cyclops gets up and speaks "ready x-men" and they battle juggernaut, at one point juggernaut runs for Iceman and icemans "ice ups" to stop the blow from juggernaut, Iceman goes flying into a wall but is ok from the protective ice... that one was for the iceman fans

... anyway the xmen manage to stop Juggernaut somehow and the xmen leave as juggernaut is taken away by special goverment team and take him away to the mutant prison...
When Juggernaut is freed by magneto i want magneto to say something like "We meet again Cain" Juggernaut is in some cell that cant be affected by his Juggernauts strength... Juggernaut is banging on the walls and magneto just grins "have a proposition to make, I will help you get revenge against your brother if you accompany my brotherhood of mutants and help me with my goal... juggernaut agrees and magneto releases him, juggernaut rampages through the jail breaking out mutants and destroying all in his way....
those are a few scenes i thought of about juggernaut...... i think it would be cool but thats my opinion