Great.
Enjoyable.
That cracks; that produces a sharp sound as of something splitting or breaking.
The formation of cracks on a surface.
The thermal decomposition of a substance, especially that of crude petroleum in order to produce petrol / gasoline.
The production of a crack sound.
Very, usually associated with praise.
Great, excellent.
To know; to understand.
To have knowledge or comprehension; discern.
To set apart; separate.
To discern; have knowledge or understanding; to know how (to).
To have personal or practical knowledge; be versed or practised; be expert or dextrous.
To spend acquired points in exchange for skills.
Capacity to do something well; technique, ability. Skills are usually acquired or learned, as opposed to abilities, which are often thought of as innate.