Get really serious really quickly (8)
I believe the answer is:
escalate
(Other definitions for escalate that I've seen before include "Cause to increase, say dispute (8)." , "mushroom" , "Increase in magnitude" , "Magnify" , "Snowball" .)
I believe the answer is:
escalate
(Other definitions for escalate that I've seen before include "Cause to increase, say dispute (8)." , "mushroom" , "Increase in magnitude" , "Magnify" , "Snowball" .)