When dr strange defeated inbetweener he was backed by lord chaos and master order... The inbetweeners masters.... Ibs powers are based upon balancing all things
After defeating him the masters sealed inbetweener in the nexus of realities where all things are already balanced. Inside that realm ib was sealed in a special prison that was unbalanced so his powers would still work. With thanos help they battered the prison and freed ib who then found himself powerless in this odd realm where law and order meet
__________________ Quotes from Hia8:
"I claimed that the science is sometimes faulty."
"You don't understand. This is fiction. That means none of this stuff really happened."
"There is no writer to purposely ignore a character's natural ability just because it suits the story."
"in some cases because the writer knows that Character A will dominate Character B easily and refuses to allow this to happen for the sake of the story."