A cheap, evasive threat that replaces itself and functions offensively and defensively is strong, but the artifact card type makes this appealing to a broad range of decks
Flooding your opponents hand with land cards beats the hell out of just drawing them cards, and youll always get to see what nonland theyre about to draw
Primus is a great value card but value is not the thing when you pass the six mana point
Chandra, Fire of Kaladesh / Chandra, Roaring Flame Chandra, Fire of Kaladesh misses on too many knobs to make much of an impact
Madness: Fiery Temper, Grave Scrabbler, Ichor Slick, Reckless Wurm, Stensia Masquerade, Strength of Lunacy Madless lets you cast spells at unexpected times, but you need mana to do it
Poppet Stitcher Poppet Stitcher is the kind of EDH card that looks pretty decent, but not downright broken at least until you play against it