Blue cards specialize in countering spells
Naturalize destroys an artifact or enchantment in a Ghave, Guru of Spores deck, but Sundering Growth and Seed Spark are probably better cards that build on the token theme of the deck
You can also use Animation ModuleAnimation Module to create Servos, and sacrifice them for mana
Costing two generic and two black, the minimum this card is likely going to give is -4/-4 in a mono-black deck
While still a decent boost, lords have been given stronger, more one-sided abilities over the year, with Goblin Chieftain from core set Magic 2010 showcasing that power creep perfectly
Cone of Cold Since I mostly play in Low and Battlecruiser, Sleep makes it into many of my decks as a potential and I hope to win the game after I swing out after Sleep resolves