Cube Cobra

Planar Cleansing > Doomskar: A three-mana wrath can't be bad, right?! Replacing a six-mana wrath (albeit, one that hits all non-land permanents), which remains in the tier one of the maybeboard.
Master Splicer > Glorious Protector: White fours have been exceptionally shallow at my power level, but recent sets have been changing that. Swapping for a powerful Restoration Angel adaption.
Frost Lynx > Saw It Coming: Frost Lynx was a mediocre creature and easily replaceable. Testing out the Foretell Cancel.
Mission Briefing > Ravenform: Mission Briefing had a low pick rate. Swapped for Ravenform, which hits almost everything.
Fanatic of Mogis > Quakebringer: Testing out this big red Sulfuric Vortex. Fanatic remains in the maybeboard.
Wicked Wolf > Battle Mammoth: Wicked Wolf was underwhelming - and most often a 4 CMC green Lightning Bolt. Swapping for Battle Mammoth, which will be effectively a 4 CMC beater.
Obzedat, Ghost Council > Firja's Retribution: Big Fs in chat for Obzedat. He'll remain in the tier one maybeboard as I test out Firja's Retribution.
Maul of the Skyclaves > Hengegate Pathway: I won't go into each of these, but cutting one card from each color for the remaining pathways (and adding back in Phyrexian Revoker to keep color distribution, which probably shouldn't have gotten the axe in the first place).
Divination > Darkbore Pathway
Draugr Necromancer > Blightstep Pathway
Relic Robber > Barkchannel Pathway
Elvish Visionary > Phyrexian Revoker