Just walking into battle? Pfeh. How pedestrian. Better to get on your bikes and ride! Your hovering future-bikes that is. Get a look at the Sky-hunter Squadron coming for The Horus Heresy in this article from Games Workshop.
From the article:
A Space Marine is a terrifying prospect on foot – a gene-wrought brute clad in ceramite, who shrugs off enemy fire and wreaks havoc in combat.
Now imagine a squadron of three of them hurtling towards the frontlines, mounted on jet-propelled flying death machines – a truly inescapable nightmare. Enter the Sky-hunter Squadron.