It happens to me often enough to annoy me
The mythic rare slot is 1/8 (or 0.125) of a slot because rares are 7/8 (see above)
Throw something scary away and your opponent will immediately be worrying about what you are keeping
Because of this, sometimes it can be hard to know exactly what value your cards have, or even what set the cards are from in some cases
Since Nexus of Fate shuffles back into your library once it goes to your graveyard, Nexus of Fate decks won by drawing their entire deck, getting some finisher on the battlefield, and then repeatedly casting Nexus of Fate to take infinite turns
Equip Ghyrson with a Basilisk Collar (or a Gorgon's Head, Gorgon Flail, or Quietus Spike) to grant him Deathtouch, and suddenly those plinks will now kill most creatures - the kind of upgrade that makes junk like a Rod of Ruin look perfectly playable