For Game 2, after seeing a card like Atarka, you might begin to employ whole deck vs
Keep in mind, Cecil is designed to transform exactly during that stabilization phase mid-game

Full Decklist: 3 Mountain 4 Forest 4 Island Arcane Signet Beast Within Become the Pilot Bigger on the Inside Bill Potts Carpet of Flowers Chaos Warp Cinder Glade Clara Oswald Command Tower Confession Dial Cultivate Cursed Mirror Dan Lewis Danny Pink Decaying Time Loop Desolate Lighthouse Dreamroot Cascade Exotic Orchard Farseek Fiery Islet Flaming Tyrannosaurus Flatline Frontier Bivouac Frost Fair Lure Fish Frostboil Snarl Fugitive of the Judoon Gallifrey Council Chamber Game Trail Graham O'Brien Growth Spiral Heaven Sent Impending Flux Into the Time Vortex Iraxxa, Empress of Mars Jenny Flint Karvanista, Loyal Lupari Last Night Together Lunar Hatchling Madame Vastra Me, the Immortal Memory Worm Myriad Landscape Nardole, Resourceful Cyborg Ominous Cemetery Osgood, Operation Double Path of Ancestry Ponder Preordain Psychic Paper Quantum Misalignment Reliquary Tower Return the Past River Song River Song's Diary Rockfall Vale Rogue's Passage Rootbound Crag Ryan Sinclair Search for Tomorrow Sheltered Thicket Sisterhood of Karn Sol Ring Sonic Screwdriver Start the TARDIS Stormcarved Coast Strax, Sontaran Nurse Surge of Brilliance Talisman of Curiosity Talisman of Impulse TARDIS Temple of Abandon Temple of Epiphany Temple of Mystery Temple of the False God The Flux The Foretold Soldier The Fugitive Doctor The Thirteenth Doctor The Twelfth Doctor Thijarian Witness Think Twice Throes of Chaos Truth or Consequences Twice Upon a Time Vineglimmer Snarl Waterlogged Grove Wreck and Rebuild Yasmin Khan 3 Mountain 4 Forest 4 Island Arcane Signet Beast Within Become the Pilot Bigger on the Inside Bill Potts Carpet of Flowers Chaos Warp Cinder Glade Clara Oswald Command Tower Confession Dial Cultivate Cursed Mirror Dan Lewis Danny Pink Decaying Time Loop Desolate Lighthouse Dreamroot Cascade Exotic Orchard Farseek Fiery Islet Flaming Tyrannosaurus Flatline Frontier Bivouac Frost Fair Lure Fish Frostboil Snarl Fugitive of the Judoon Gallifrey Council Chamber Game Trail Graham O'Brien Growth Spiral Heaven Sent Impending Flux Into the Time Vortex Iraxxa, Empress of Mars Jenny Flint Karvanista, Loyal Lupari Last Night Together Lunar Hatchling Madame Vastra Me, the Immortal Memory Worm Myriad Landscape Nardole, Resourceful Cyborg Ominous Cemetery Osgood, Operation Double Path of Ancestry Ponder Preordain Psychic Paper Quantum Misalignment Reliquary Tower Return the Past River Song River Song's Diary Rockfall Vale Rogue's Passage Rootbound Crag Ryan Sinclair Search for Tomorrow Sheltered Thicket Sisterhood of Karn Sol Ring Sonic Screwdriver Start the TARDIS Stormcarved Coast Strax, Sontaran Nurse Surge of Brilliance Talisman of Curiosity Talisman of Impulse TARDIS Temple of Abandon Temple of Epiphany Temple of Mystery Temple of the False God The Flux The Foretold Soldier The Fugitive Doctor The Thirteenth Doctor The Twelfth Doctor Thijarian Witness Think Twice Throes of Chaos Truth or Consequences Twice Upon a Time Vineglimmer Snarl Waterlogged Grove Wreck and Rebuild Yasmin Khan Masters Of Evil Finally, we've got Masters of Evil, a deck full of the biggest threats in all of time and space

As long as a card isn't banned in the format, then it is allowed
Things You Should Know Commander damage is an alternative win condition in the Commander (EDH) format
Special Rules for Pokmon LV