Day // Night Card // Card Day Card (If it becomes day or night or if a daybound permanent enters the battlefield, track day/night for the rest of the game.) As it becomes day, transform all nightbound permanents
Each companion comes with a restriction on how your deck must be constructed

Acidic Soil Avenger of Zendikar Bioengineered Future Blackblade Reforged Blanket of Night Bountiful Harvest Branch of Boseiju Brass's Bounty Bumi, Eclectic Earthbender Cleansing Coastline Marauders Crystalline Armor Culmination of Studies Dingus Egg Drain Power Drown in Filth Dune Chanter Dune-Brood Nephilim Earth Surge Elsewhere Flask Eluge, the Shoreless Sea Emergent Sequence Equipoise Eumidian Wastewaker Every Dream a Nightmare From the Ashes Garruk, Primal Hunter Gerrard's Verdict Gerrymandering Great Divide Guide Hazezon Tamar Herald of Leshrac Joyous Respite Knight of the Reliquary Krenko's Buzzcrusher Land Equilibrium Lightstall Inquisitor Lluwen, Imperfect Naturalist Mana Flare Mana Seism March from Velis Vel Michelangelo, On the Scene Multani, Yavimaya's Avatar Nahiri's Lithoforming Naya Obsidian Charmaw Omo, Queen of Vesuva Orcish Squatters Avatar Ore-Scale Guardian Patient Rebuilding Phabine, Boss's Confidant Power Surge Pygmy Hippo Rain of Filth Rampaging Brontodon Rumbleweed Shimmer Stench of Evil Strata Scythe Tazeem Tectonic Reformation Terraformer Tsabo's Web Urborg, Tomb of Yawgmoth Vision Charm Walker of the Wastes Wave of Vitriol Worm Harvest Yavimaya, Cradle of Growth Yuma, Proud Protector Zanarkand, Ancient Metropolis Zanarkand, Ancient Metropolis

As your opponent will be forced to deal with your characters in order to keep you from rushing to twenty lore too quickly, many, many of your characters will be banished