This deck does not appear to be legal in Standard (Season from Sep 2021).
Problems: You cannot play more than 4 of: Lovestruck Beast // Heart's Desire, Bonecrusher Giant // Stomp, Kazandu Mammoth // Kazandu Valley, Shatterskull Smashing // Shatterskull, the Hammer Pass, Edgewall Innkeeper, The Akroan War, Ox of Agonas, Heartless Act, The Great Henge, Mystical Dispute, Brushfire Elemental, Negate, Fire Prophecy, Embercleave, Vivien, Monsters' Advocate, Questing Beast, Wilt, Scavenging Ooze, Extinction Event, Bloodchief's Thirst, Skyclave Shade, Cling to Dust, Thieves' Guild Enforcer, Soul Sear, Soaring Thought-Thief, Ruin Crab, Embereth Shieldbreaker // Battle Display, Elspeth's Nightmare, Eliminate, Drown in the Loch, Ugin, the Spirit Dragon, Skyclave Apparition, Shark Typhoon, Phoenix of Ash, Omen of the Sea, Mazemind Tome, Into the Story, Elspeth Conquers Death. · Not legal in this format: Lovestruck Beast // Heart's Desire, Bonecrusher Giant // Stomp, Kazandu Mammoth // Kazandu Valley, Shatterskull Smashing // Shatterskull, the Hammer Pass, Edgewall Innkeeper, The Akroan War, Ox of Agonas, Heartless Act, The Great Henge, Mystical Dispute, Brushfire Elemental, Fire Prophecy, Embercleave, Vivien, Monsters' Advocate, Questing Beast, Wilt, Scavenging Ooze, Extinction Event, Bloodchief's Thirst, Skyclave Shade, Cling to Dust, Thieves' Guild Enforcer, Soul Sear, Soaring Thought-Thief, Ruin Crab, Embereth Shieldbreaker // Battle Display, Elspeth's Nightmare, Eliminate, Drown in the Loch, Ugin, the Spirit Dragon, Skyclave Apparition, Shark Typhoon, Phoenix of Ash, Omen of the Sea, Mazemind Tome, Into the Story, Elspeth Conquers Death, Yorion, Sky Nomad, Wicked Wolf, Trail of Crumbs, Tangled Florahedron // Tangled Vale, Merfolk Windrobber, Lullmage's Domination, Gilded Goose, Feasting Troll King, Emeria's Call // Emeria, Shattered Skyclave, Doom Foretold, Chainweb Aracnir, Agadeem's Awakening // Agadeem, the Undercrypt, Treacherous Blessing, Scorching Dragonfire, Of One Mind, Neutralize, Jwari Disruption // Jwari Ruins, Brazen Borrower // Petty Theft, Beanstalk Giant // Fertile Footsteps, Agonizing Remorse, Woe Strider, Witch's Oven, Solemn Simulacrum, Shredded Sails, Shadows' Verdict, Selfless Savior, Robber of the Rich, Rankle, Master of Pranks, Primal Might, Omen of the Sun, Lurrus of the Dream-Den, Luminarch Aspirant, Kroxa, Titan of Death's Hunger, Kogla, the Titan Ape, Klothys, God of Destiny, Heliod's Intervention, Hagra Mauling // Hagra Broodpit, Giant Killer // Chop Down, Garruk, Unleashed, Didn't Say Please, Cultivate, Ashiok, Nightmare Muse, Archon of Sun's Grace, Zareth San, the Trickster, Spikefield Hazard // Spikefield Cave, Speaker of the Heavens, Seasoned Hallowblade, Rimrock Knight // Boulder Rush, Murderous Rider // Swift End, Lochmere Serpent, Korvold, Fae-Cursed King, Elder Gargaroth, Atris, Oracle of Half-Truths, Alseid of Life's Bounty.