If I could get it done, the card pile-up would go like this:
I lay down an Abhorrent Overlord (6/6)
I place two Dark Favors for a +6/+2 total
I place two Scourgemarks for +2/+0 total
I have an Erebos's Emissary used as an enchantment for +3/+3
If I sacrifice a creature card, then an extra +2/+2 is placed
I have a Terrus Wurm that I can scavenge, placing a +5/+5 counter on choice creature(as a sorcery)
so in total, the final monster is a 24/18 at full strength...
and then I can cipher a Midnight Recovery and Shadow Slice to it.