Have this extract instead: When they cross the threshold, the world doesn't shake and the air's not any colder than it was three feet before. Shouto ties the length of rope around his wrist, keeps his ears out for whatever has Dr Iida looking like he's about to go from zero to one twenty-five in the next three seconds. Midoriya hasn't stopped smiling since they crossed.
Eventually Shouto has the rope tight around him, tugs at it so Midoriya knows he's ready. The wind hasn't quite picked up but something definitely has him feeling apprehensive. Dr Iida turns around, gives what's supposed to be a cheeky grin to Midoriya but the angles of his jaw just make it seem like he's about to murder the kid, "We don't stop until we're in the safe zone, okay Izuku?"
Midoriya isn't looking at Shouto when he smiles back, bright and impish and absolutely menacing, "Last one to the top?"
"Naturally."
That apprenhension in Shouto's gut must be really bad because it feels like the ground's shaking beneath his feet. The good doctor gives him a last look and mumbles, "Be careful," in Shouto's direction before he's running for one of the overhanging rocks poking out from what's undoubtedly feet of snow.
Izuku's smile is less edgy when he turns to Shouto, "We should get going too. Getting wiped out isn't a lot of fun, trust me."
Shouto's too busy paying attention to the quiet roaring that's echoing in his ears, the shaking that's becoming a gluttonous rumbling beneath him, "Midoriya," he says, "What's going on?"
That smile is back, toothy, too-wide, absolutely shit-eating, "We're out-running an avalanche."