It sounds simple, but it completely shuts down the haste-based racing decks and disrupts the artifact mana rocks that Ramp decks rely on

You can view the entire Commander deck below: Creatures (23) 1 Windborn Muse 1 Ichor Rats 1 Ichorclaw Myr 1 Plague Stinger 1 Blight Mamba 1 Viridian Corrupter 1 Plague Myr 1 Mycosynth Fiend 1 Phyrexian Swarmlord 1 Scavenging Ooze 1 Grateful Apparition 1 Evolution Sage 1 Myr Convert 1 Ixhel, Scion of Atraxa 1 Glissa's Retriever 1 Contaminant Grafter 1 Norn's Choirmaster 1 Vishgraz, the Doomhive 1 Blightbelly Rat 1 Bilious Skulldweller 1 Cankerbloom 1 Pestilent Syphoner 1 Venomous Brutalizer Lands (38) 8 Forest 6 Plains 6 Swamp 1 Sungrass Prairie 1 Tainted Wood 1 Tainted Field 1 Krosan Verge 1 Exotic Orchard 1 Bojuka Bog 1 Command Tower 1 Temple of Silence 1 Temple of Plenty 1 Temple of Malady 1 Sandsteppe Citadel 1 Myriad Landscape 1 Canopy Vista 1 Fortified Village 1 Path of Ancestry 1 Karn's Bastion 1 Shineshadow Snarl 1 Necroblossom Snarl Spells (39) 1 Ghostly Prison 1 Swords to Plowshares 1 Sol Ring 1 Fellwar Stone 1 Night's Whisper 1 Golgari Signet 1 Putrefy 1 Mortify 1 Trailblazer's Boots 1 Cultivate 1 Contagion Clasp 1 Grafted Exoskeleton 1 Carrion Call 1 Phyrexian Rebirth 1 Norn's Annex 1 Beast Within 1 Caress of Phyrexia 1 Noxious Revival 1 Chromatic Lantern 1 Merciless Eviction 1 Commander's Sphere 1 Painful Truths 1 Fumigate 1 Moldervine Reclamation 1 Arcane Signet 1 Culling Ritual 1 Glistening Sphere 1 Wurmquake 1 Phyresis Outbreak 1 Geth's Summons 1 Norn's Decree 1 Noxious Assault 1 Unnatural Restoration 1 Expand the Sphere 1 Feed the Infection 1 Vraska's Fall 1 Phyrexian Atlas 1 Vat Emergence 1 Infectious Inquiry Phyrexia: All Will Be One is scheduled to release on February 10

In simple terms, as its name suggests, the Expanded formats value proposition offers an environment with many more deckbuilding possibilities than the current Standard format
A 3/3 is a very healthy blocker and the ability to untap lands so as to allow more spells and more loyalty to keep him alive is exceptional
Because it was never included in standard booster packs, only a very limited number of copies were distributed, making it extremely rare
You have some slow lands in here, have you considered switching bounce lands and surveil lands for filter lands and Pathways