Pretty weak to just about any form of UU stall. Standard Venusaur + Milotic + Fire + Spinner + Ghost (especially if it has Will-O-Wisp) + Spikes can just switch around without having to predict at all, grab a layer here and there and then wear you down. Absol is more or less your best shot at breaking it, but bulky Hitmontop is so common so I wouldn't count on coming out on top (HAH a pun), plus Rotom or Mismagius can simply Will-O-Wisp you.
There are a couple of really easy things you can do to fix this up. For one, you can just run Psycho Cut in Night Slash's place on Absol so that you don't have to worry about Hitmontop or Weezing from walling you. Secondly, I think you could do pretty well with Swords Dance Blaziken in Primeape's place. After a boost you can OHKO Milotic with Superpower, and then just blast pretty much any other stall Poke in sight. This works especially well with Psycho Cut on Absol since eliminating Hitmontop / Weezing will definitely be handy. Also a FWG core of your own will definitely not hurt at all when trying to take on the likes of Venusaur.