"Confirm the four hours, see if there's any gap. Go out to three hours fifty-six minutes and see if the border contracts as time passes, figure out how the clock stops and starts." Did it, for example, care if you went out to three hours and fifty-six minutes, waited for fifteen, and then moved forward again? Did it return you on the first step or after four minutes. "I'd test the 'ceiling' but I can't fly without being a bird, and birds are worse than cats for serious spellwork."

Admitting any limitation to Stark was a calculated risk. Most likely the man already know Loki couldn't fly independently, but if he didn't it was handing him some useful tactical knowledge. The slight illusion of openness, however, might pay dividends down the road. "In my experience, there are always holes and folds in borders. Some aren't exploitable," the Isle of Silence was hell for that - holes everywhere, leading nowhere but back where you started in silence so deep it suppressed the other senses too, "others are. It's a matter of finding them."