shadow realm

noun3

1. •
   Knocked out, rendered unconscious.

   • UFC welterweight star Jorge Masvidal knows a thing or two about sending his opponents to the shadow realm, and he explained what happens when they go there. — 2019
2. •
   (slang) Oblivion; death.
3. •
   Alternative letter-case form of Shadow Realm (“a place that is inhabited by darkness, evilness or malevolent entities and creatures, sometimes based around, or said to be, shadows or personifications thereof”).