Well, in my experience, unless youre going hard on enabling your catch-up ramp (which Ill cover later in the article), it starts to drop off in value as soon as you go above two mana
While Disguise can be a highly effective tool in any players arsenal, especially those willing to play mind games, finding ways to disguise your cards outside of inbuilt effects can be a challenge
If you choose the second mode, Slight Malfunction goes on the stack without any targets
If tails, that attack does nothing

Abandon Attachments Abstract Paintmage Adeliz, the Cinder Wind Aegar, the Freezing Flame Aetherwing, Golden-Scale Flagship Alania, Divergent Storm Ant-Man, Elusive Avenger Arcane Infusion Arjun, the Shifting Flame Armor Wars Ashling's Command Astonishing Spider-Man Balmor, Battlemage Captain Baral and Kari Zev Battle of Frost and Fire Baxter Stockman Beacon Bolt Beamsplitter Mage Bilbo, Retired Burglar Blast of Genius Blistercoil Weird Bloodwater Entity Boosted Sloop Breeches, the Blastmaker Bria, Riptide Rogue Brilliance Unleashed Broadside Barrage Brudiclad, Telchor Engineer Brutal Expulsion Bucket List (playtest) Call the Skybreaker Captain Howler, Sea Scourge Captain Storm, Cosmium Raider Captain Vargus Wrath Catch // Release Cerebral Vortex Channeled Force Chaos Mutation Chemister's Trick Clout of the Dominus Cloven Casting Collected Conjuring Colorstorm Stallion Compleated Conjurer Corporeal Projection Counterflux Crackleburr Crackling Drake Crag Puca Creative Outburst Cryptic Pursuit Culmination of Studies Cunning Strike Cutthroat Negotiator Cyclops Superconductor Dack Fayden Dack's Duplicate Dalakos, Crafter of Wonders Detective's Satchel Djinn Illuminatus Dominus of Fealty Don & Raph, Hard Science Double Negative Dracoplasm Dragonfly Swarm Dragonshift Eclipsed Flamekin Ecstatic Electromancer Effortless Master Electrolyze Electrosiphon Elemental Expressionist

On top of the nine different versions of Teferi, Master of Time, Core Set 2021 will also feature what Rosewater called vertical cycles of cards, meaning groups of cards that form a cycle within the same color