Signs of a fake Pokemon card Paper quality: Authentic cards have a specific texture and often show a black core line when cut (the "black line test") Color and print: Counterfeits are often too dull or overly shiny
Machine God's Effigy AND March of Progress Hitting roughly halfway on my list are these two similar cards that are both rocking a Blue color identity

Ashad, the Lone Cyberman Ashling, the Limitless Astrid Peth Bag of Devouring Baloth Prime Biotech Specialist Blood Aspirant Blood Hypnotist Bloodbriar Body Dropper Burdened Aerialist Camellia, the Seedmiser Captain Lannery Storm Captain Lannery Storm Crime Novelist Desert Warfare Dina, Essence Brewer Dragon Appeasement Effluence Devourer Eloise, Nephalia Sleuth Esoteric Duplicator Evendo Brushrazer Experimental Confectioner Fleeting Memories Fleshtaker Forge Boss Furnace Celebration Giant Fly Gixian Infiltrator Gleaming Geardrake Gluttonous Guest Graf Mole Havoc Jester Hearthhull, the Worldseed Jenny Flint Juri, Master of the Revue Kels, Fight Fixer Kingpin, Wilson Fisk Korvold, Fae-Cursed King Lazav, Wearer of Faces Lightless Evangel Lonis, Genetics Expert Magnetic Snuffler Martha Jones Moonstone Eulogist Narci, Fable Singer Nuka-Cola Vending Machine Persuasive Interrogators Piper Wright, Publick Reporter Pirate Peddlers Popular Egotist Prowling Geistcatcher Rakdos, the Muscle Rapacious Guest Ravenous Squirrel Riveteers Ascendancy Rose, Cutthroat Raider Ruthless Deathfang Sandbender Scavengers Sanguine Brushstroke Sanguine Statuette Savra, Queen of the Golgari Scavenger's Talent Scouring Swarm Senator Peacock Sierra, Nuka's Biggest Fan Skittering Precursor Slaughter-Priest of Mogis Slayer's Bounty Smothering Abomination Sorcerer's Broom Szarel, Genesis Shepherd

Vintage, slabs, chase cards, sealed, and bulk are treated differently
A scanner that misses variants gives you confidently wrong values
Absolutely iconic