abstruseness
arduousness
bothersomeness
burdensomeness
complexity
complexness
complication
convolution
crabbedness
crampedness
deepness
difficultness
difficulty
entanglement
esoterica
hairiness
hardness
intricateness
involution
involvement
knottiness
laboriousness
onerousness
oppressiveness
perplexity
profoundness
profundity
ramification
reconditeness
rigor
rigorousness
ruggedness
strenuousness
subtlety
tanglement
technicality
toilsomeness
toughness
troublesomeness
clearness
contradiction
diversity
elaboration
elegance
ingenuity
mastery
maze
multiplicity
mystery
nicety
nuance
obscurity
peculiarity
rapidity
regularity
richness
working