WHITE | BLUE | BLACK | RED | GREEN MULTICOLORED | ARTIFACT | LAND | ALL CARDS WHITE Coppercoat Vanguard Deification Harnessed Snubhorn Metropolis Reformer Spark Rupture Tazri, Stalwart Survivor BLUE Filter Out Tolarian Contempt Training Grounds Vesuvan Drifter BLACK Ayara's Oathsworn Blot Out Death-Rattle Oni Markov Baron Urborg Scavengers RED Arni Metalbrow Kolaghan Warmonger Plargg and Nassari Reckless Handling GREEN Animist's Might Leyline Immersion Nissa, Resurgent Animist Open the Way Tranquil Frillback Undercity Upheaval MULTICOLORED Calix, Guided by Fate Campus Renovation Cosmic Rebirth Danitha, New Benalia's Light Feast of the Victorious Dead Gold-Forged Thopteryx Jirina, Dauntless General Jolrael, Voice of Zhalfir The Kenriths' Royal Funeral Kiora, Sovereign of the Deep Nahiri, Forged in Fury Nahiri's Resolve Narset, Enlightened Exile Nashi, Moon's Legacy Niv-Mizzet, Supreme Ob Nixilis, Captive Kingpin Pia Nalaar, Consul of Revival Rebuild the City Rocco, Street Chef Samut, Vizier of Naktamun Sarkhan, Soul Aflame Sigarda, Font of Blessings Tyvar the Bellicose ARTIFACT Karn, Legacy Reforged LAND Drannith Ruins WHITE | BLUE | BLACK | RED | GREEN MULTICOLORED | ARTIFACT | LAND | ALL CARDS

The Rat King has one toxic himself, and hell give any other rats you control one toxic
If the creature is copied, the copy won't have indestructible (unless the creature otherwise has indestructible).
Many of Magic's most iconic cards, like Lightning Bolt, Sol Ring, and the Power 9, were all included in Alpha
That's when this became really easy
It's almost always the right answer to use extra mana in the early game to discard this card, gain some extra life, thin your deck of lands, and make sure you continue ramping