Superheroic doesn't necesscerily mean easy. The last fight of Prototype involves leaping 100 feet in the air and throwing helicopters at a 15 foot mutant, but it isn't exactly easy, especially since there is a time limit on it before a nuke goes off.
Even Deathwatches rather anemic Space Marines can pick up an SUV and throw it at someone.
I expect to see grapple moves involving picking up a chaos marine and throwing him bodily through buildings.
Chase scenes that look like this:-
with Marines punching through reiforced walls without slowing down. Leaping off tall things and have the pavement shatter around you on impact.
Fights against mooks that look like this:-
http://www.youtube.com/watch?v=8ZYzsQhm9tU#t=2m44s
with Marines playing the role of Sauron, flinging clumps of mortals aside with every swing of their chainsword. Imagine the collateral damage caused when two Saurons have a punch up in a location with lots of destructable scenery!
Marine fights should topple buildings, fling buses on to hard to reach places and generate craters tens of feet deep.
Win or lose, the landscape will remember that a Marine fought here.
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I don't feel it is to much to ask that Marines at least have a go at living up to their hype as the finest warriors in the universe, ultimate warriors able to take on a modern infantry division with ease. Yknow, Legendary.

