면 날라가다

if X, it's gone

A conditional "-(으)면" plus 날라가다, the common spoken spelling of 날아가다 "fly away". Sometimes it is literal flight — if it flies off, whoever sent it flying has to drink again. More often it means wiped out: China could get blown away if it plays a game of chicken, once they cut it it's gone, if you get caught it's over. It is casual speech; in writing you would see 날아가다.

Register: casual spoken