for one's life
for dear life
like one's life depended on it
hard up
despo
overdesperate
in the worst way
cry for
cry out for
in extremis
do-or-die
desperate
imperious
acute
scamblingly
time-sensitive
clamant
snorter
ultraurgent
hard as iron
dys-
fiendish
mountainous
harder than Chinese math
murderous
hard as Chinese algebra
superdifficult
cry
superurgent
frenzy
yearned-for
frantically
time-critical
big
longed-for
wished-for
despairingly
despondently
make hard work of
hurry
craved
desired
tall
flounder
desperation
rough
torrid
tightrope
ambitious
choosy