There are 10 attractions at Epcot we rate as "Not To Be Missed":

Not To Be Missed at Epcot
Future World Living with the Land
Mission: SPACE Green
Mission: SPACE Orange
Spaceship Earth
Sum of All Thrills (in Innoventions East)
Test Track
Turtle Talk with Crush
World Showcase IllumiNations: Reflections of Earth
The American Adventure

Not To Be Missed Attractions at Other Parks