This deck does not appear to be legal in Standard (Season from Sep 2021).
Problems: You cannot play more than 4 of: Bonecrusher Giant // Stomp, Heartless Act, Shatterskull Smashing // Shatterskull, the Hammer Pass, Negate, Mystical Dispute, Shark Typhoon, Ox of Agonas, Lovestruck Beast // Heart's Desire, Goldspan Dragon, The Akroan War, Kazandu Mammoth // Kazandu Valley, Duress, Omen of the Sea, Extinction Event, Embercleave, Edgewall Innkeeper, Binding the Old Gods, Valki, God of Lies // Tibalt, Cosmic Impostor, Skyclave Shade, Saw It Coming, Elspeth's Nightmare, Eliminate, Brushfire Elemental, Bloodchief's Thirst, Behold the Multiverse, The Great Henge, Shadows' Verdict, Scavenging Ooze, Jwari Disruption // Jwari Ruins, Frost Bite, Fire Prophecy, Disdainful Stroke, Cultivate, Cling to Dust, Brazen Borrower // Petty Theft. · Not legal in this format: Bonecrusher Giant // Stomp, Heartless Act, Shatterskull Smashing // Shatterskull, the Hammer Pass, Mystical Dispute, Shark Typhoon, Ox of Agonas, Lovestruck Beast // Heart's Desire, Goldspan Dragon, The Akroan War, Kazandu Mammoth // Kazandu Valley, Omen of the Sea, Extinction Event, Embercleave, Edgewall Innkeeper, Binding the Old Gods, Valki, God of Lies // Tibalt, Cosmic Impostor, Skyclave Shade, Saw It Coming, Elspeth's Nightmare, Eliminate, Brushfire Elemental, Bloodchief's Thirst, Behold the Multiverse, The Great Henge, Shadows' Verdict, Scavenging Ooze, Jwari Disruption // Jwari Ruins, Frost Bite, Fire Prophecy, Cultivate, Cling to Dust, Brazen Borrower // Petty Theft, Yorion, Sky Nomad, Ugin, the Spirit Dragon, Thieves' Guild Enforcer, Soaring Thought-Thief, Skyclave Apparition, Showdown of the Skalds, Ruin Crab, Robber of the Rich, Questing Beast, Phoenix of Ash, Mazemind Tome, Into the Story, Giant Killer // Chop Down, Emergent Ultimatum, Drown in the Loch, Woe Strider, Wilt, Vivien, Monsters' Advocate, Soul Sear, Shredded Sails, Scorching Dragonfire, Rimrock Knight // Boulder Rush, Merfolk Windrobber, Kroxa, Titan of Death's Hunger, Koma, Cosmos Serpent, Klothys, God of Destiny, Fervent Champion, Emeria's Call // Emeria, Shattered Skyclave, Embereth Shieldbreaker // Battle Display, Elspeth Conquers Death, Claim the Firstborn, Alrund's Epiphany, Agadeem's Awakening // Agadeem, the Undercrypt, Vorinclex, Monstrous Raider, Village Rites, Usher of the Fallen, Tangled Florahedron // Tangled Vale, Soul Shatter, Shepherd of the Flock // Usher to Safety, Selfless Savior, Seasoned Hallowblade, Sea Gate Restoration // Sea Gate, Reborn, Of One Mind, Mire Triton, Lurrus of the Dream-Den, Luminarch Aspirant, Lullmage's Domination, Fireblade Charger, Elder Gargaroth, Chainweb Aracnir, Beanstalk Giant // Fertile Footsteps, Anax, Hardened in the Forge, Agonizing Remorse, Toski, Bearer of Secrets, Torbran, Thane of Red Fell, Reidane, God of the Worthy // Valkmira, Protector's Shield, Rankle, Master of Pranks, Polukranos, Unchained, Masked Vandal, Kiora Bests the Sea God, Immersturm Predator, Egon, God of Death // Throne of Death.