Islam humiliates another BJJ black belt (who give him? We have to check that one). I know Islam has his own weapons (wrestling, judo, sambo) but not even Sakuraba was this hellbent on embarrassing the pajama boys like Islam (Moicano, Poirier, Oliveira, Moises, Hooker, Dober). Islam is pretty much out of challengers at 155. Short of Ilia Topuira coming up from 145 or reaching down and grabbing Paddy Pimblett for the meme value, Islam's only plays are to pull a Khabib and retire or make the move up to 170.
Likewise, Merab has no clear challengers except for do-overs against Yan or O'Malley.