The phrase "blow sky high" is typically used to describe a situation where something is completely destroyed or ruined. However, there are several antonyms for this phrase, which suggest the opposite of destruction and ruin. Some of these antonyms include "preserve," "save," "protect," "strengthen," "fortify," "secure," and "restore." These words are used to denote a sense of safety, stability, and security. They imply that something is being safeguarded, strengthened, or brought back to its former state. Thus, while "blow sky high" conveys a sense of destruction and chaos, its antonyms provide a sense of hope, resilience, and preservation.