Speed Darkrai skeleton? I'd play something like this:
4 Darkrai
4 Sableye
4 Juniper
4 N
5 Random Receiver/Skyla/Bianca (in any combination)
1 Computer Search ACE SPEC
4 Catcher
4 Dark Patch
4 Energy Switch
1 Energy Search
4 Ultra Ball
8 Dark Energy
That's 49 cards. Your main tech options for the last 11 cards are:
Keldeo EX to avoid locks (either retreat lock or paralysis lock)
More energy (I'd play 10 energy and 1 energy search MINIMUM, but if you decide to play tech attackers they might use non-Dark energies)
More supporters (I'd play 1 or 2 more than I have in the skeleton myself, but you don't need to and can easily be fine with 13 supporters)
Crushing+Enhanced Hammers to deny opponents energy (you can reuse these with Sableye for great effect)
Eviolite(s) to avoid KOs from Terrakion/Rayquaza EX and 2HKOs from other EXs
Potions/Max Potions/SSU to heal off damage and avoid 2HKOs
Tool Scrapper(s) to get rid of opposing Eviolites and Garbodor
Pluspowers and/or Dark Claw to do more damage
Terrakion or Landorus EX with fighting and/or prism energy.
1 Revive OR Super Rod (I wouldn't play any more than this since it's really not needed in the first place, as you have enough attackers for a whole game and can get energy out of the discard with Dark Patch. Really wouldn't play either of these myself, but if you want to test it you can find out that it's a waste fo a space on your own =P)
DCE and Mewtwo EX because it's a really good attacker with DCE and energy switch