Thoracle is the premier win condition in cEDH, and also just a very anticlimactic card to play against in casual games
Their present state is truly horrific, like something out of a Saw film
Eldrazi Incursion from Modern Horizons 3 is a great example of a deck that rehashes an established theme of an already-existing precon but does so in a way that feels unique
Don't forget about the clues and lessons that are core to the set, and of course, the legendary characters Appa, Steadfast Guardian, Wan Shi Tong, Librarian and The Lion-Turtle
The first was Library of Leng, first printed in Limited Edition Alpha , whose text says, There is no limit to size of your hand. In subsequent reprintings, most notably in Revised Edition , the text was changed to You must skip the discard phase of your turn--as if that was a bad thing