It was as if her legs had turned to ice.
She tried to stand but her legs had turned to grass.
He dropped as though his legs had turned to liquid beneath him.
She rushed outside, only to find her legs had turned to water.
"The man was so relieved his legs turned to jelly."
Both legs turned the color of a deep bruised blue.
He tried to back away from them, but his legs had turned to rubber.
She took a step back from him before her legs turned completely to butter.
It felt as if my legs had turned to warm lead.
His legs turned to water and then began to evaporate from under him.