resource
resourcefulness
hard as nails
rise to the challenge
trouble
rise to the occasion
problem
hard time
rough sledding
contend
killer
challengeable
rigour
hard-set
struggler
enmesh
copout
uphill
counterdifficulty
over the river and through the woods
endurance
trickiness
imagination
blaze
difficulty level
enodation
superchallenge
hell
hit
entangled
catch a cold
hard yards
underchallenge
obstinacy
challenge
challengeful
challengingly
mulishness
stubbornness
pull off
counseling
hard
obstinance
have a mountain to climb
run for one's money
difficult
testingly
pain point
hardpressed
throe
succor
daunting
torfer
multichallenge
ministration
relief
succour
in trouble
torrid
rise
skittish
formidable
hash out
frustrable
challenging
push shit uphill
adroitly
stumblingblock
solvability
square one's shoulders
an old dog for a hard road
fighter
clutch
oppressiveness
struggling
heaviness
master key
doo-doo
obstacle-ridden
painstakingness
conscientiousness
onerousness
rocky
toughness
manage
intractable
burdensomeness
leg up
formidability
difficultness
tortured
plucky
challengee
queer someone's pitch
winning
gutsy