The cards created to fight the Werewolves are either instant or cheap
These come in various sizes, from 200-count boxes ideal for commons to massive 5,000-count boxes for extensive collections
Or maybe you want the Elven Council deck, and force your table to do a whole lot of voting
Convert to Slime gives you a three for one, and if you have Delirium, you get a fonky chonky Ooze for your troubles, making it a four for one, for five mana
Even amongst some of the most respected collectors there are disagreements about what a misprint should be called
The MTG multiverse is on full display as new characters clash with old, some who've even received a full-on Western makeover