Aldrick's foot bridge

The air under your feet becomes solid ground. You and 1 willing creatures you touch find yourself's unable to descend. You can walk across areas where there is no ground. You can also walk up as if there were stairs but you can't walk down. The only noise you make is a quiet wind from the bottom of your feet.  If you are in a situation where there is no air like underwater the spell fails. Every level higher you cast this spell you can target one extra creature.