You CAN Play Type I #125: Deconstructing Darksteel, Part II – Artifacts
Geth’s Grimoire
Lots of beginners who want to build Rack decks oooh and aaaah when they see Megrim. Thing is, unloading your discard on the opponent is top priority, so your opponent has no hand by the time you have a moment to remember to play Megrim. At that point, a creature cleans up far better.
Geth suffers from the Megrim problem as well.