problematic

(s) open to doubt or debate
- If you ever get married, which seems to be extremely problematic
debatable, problematical,
(s) making great mental demands; hard to comprehend or solve or believe
- a baffling problem
- I faced the knotty problem of what to have for breakfast
- a problematic situation at home
baffling, knotty, problematical, elusive, tough,

debatable problematical baffling knotty elusive tough

problematical problematically