The most difficult game I have played from last-gen are:
Dead Space 1-2 on the hardest difficulty
Skyrim on Legendary ( OMGoodness -_- )
All the Silent Hill’s are insanely hard....... It has the hardest puzzles in the history of all puzzles ever made.
Gears Of War 1 2 3 on Insane.
God Of War games were also insanely hard on the hardest difficulty even GOW:Ghost of Sparta (PSP)
Dark Souls ...... enough said.