Endless magical event engages worker, like some mysticism (7)
I believe the answer is:
tantric
'like some mysticism' is the definition.
(relating to tantras, mystical texts)
'endless magical event engages worker' is the wordplay.
'endless magical event' becomes 'tric' (I can't justify this - if you can you should believe this answer much more).
'engages' indicates putting letters inside.
'worker' becomes 'ant' (worker is a type of ant).
'tric' placed around 'ant' is 'TANTRIC'.
Can you help me to learn more?
(Other definitions for tantric that I've seen before include "Of Hindu/Buddhist ritual" , "of meditating?" , "Relating to Hindu mysticism" , "Relating to Hindu or Buddhist mystical texts" , "Coming from religious writing" .)