Hardest bits these days are all towards the end when you are back towards the Red Route and can be avoided if necessary. Double X, The Bitch and Wormhole all have short sections that are a bit harder than the Red
+1, although relative to the red I’d say “quite a bit harder”, lots more steps, rocks and rough bits compared to the really fast bermed stuff on the red and blue decents that almost parralel them.
The bulk of it is more like a less manicured red, more like a red that’s been used enough to have roots showing through, the odd natural drop off, flat corners etc and generaly made up of actual singletrack rather than being 2ft wide.
I’d actualy rather do the black then climb back upto the red or blue after spooky wood/before betty blue once you’ve done Redemption.