• 2 Alchemist's Apprentice – it’s a solid card, good blocker and can net you a card I would up to 4
• 2 Artisan of Kozilek – personally I think its overrated, it can be chumped and removed/bounce for the mana cost you want something with more staying power.  Sphinx of Jwar Isle is a good option it has evasion and will take mass removal to deal with it if it sticks.  I would switch them
• 2 Bloodhunter Bat – I would lose for the other 2 alchemists apprentice
• 1 Gaurd Gomazoa – I would up the count to 3 replacing the wall of blood below
• 1 Massacre Wurm – he can stay
• 2 Mist Raven – bouncing a creature is good, however, controlling your draws would be more beneficial in this deck I would switch it out for sage owl
• 2 Nezumi Graverobber – switch out for two more sage owls
• 1 Ravenous demon – for the reasons mentioned above he can go.
• 1 Reaper from the Abyss – he can stay, changing some of the spells below can offer more morbid options
• 1 Sakashima's student – copying others always fun, but it might be better sideboard
• 2 Wall of blood –replace with the guard
• Revised creature count -- 16

• -Spells-
• 2 Crucible of worlds – lose and add two more rits.
• 2 Dark Ritual  -- see above
• 2 Disperse  -- bounce good
• 2 Essence Harvest – if you get a beat out it will be beneficial, but keep it at two no point getting to many in your hand at once without the beat. 
• 1 Exquisite blood – lose, without a constant life gain its useless
• 1 Haunting Echoes – as mentioned above lose this
• 1 Howling mine – I like card draw, but not for my opponent, especially since it will take time to build up your mana no reason to help them out
• 1 Icy Manipulator – lose better to remove permantly then tap
• 1 Panoptic Mirror – comes to late, especially as a 1 of
• 2 Peel from Reality – ideally you’ll hit the sage owls if you make that switch
• 2 Rite of Consumption – As with essence harvest it is beneficial, if you get a beat, but you don’t need both especially with  the sac as you won’t use it while your winning
• 2 Switcharoo – your not going to give up your beats nor your early defense-switch for some doom blades or go for the throat
• 2 Time Warp – I am going back and forth about this, double turns is always a good thing, but you will need more control options to buy you time.  So I would lose them
• 1 Traumatize – bye bye
• 2 Unsommon – ok

If you make these switches you are left with 14 open slots.  I’ll leave it up to you on how to fill them
but I would look at removal and control. 
4 copies of recoil would be great as would mana leaks.  I would also leave 3 slots open for stitch
together, with the control spells odds are you will get threshold easily