I am very unsure of going down to three Downfalls, but maybe we are supposed to sideboard the fourth, perhaps instead of the second Aetherspouts, or possibly even the second Tasigur
It's also pricey, and its never been reprinted
Throw in the fact it can double as a surprisingly flexible reanimation spell and you have one of the best Limited cards in MTG Foundations
If you gain an amount of life "for each" of something or "equal to the number" of something, that life is gained as one event and Leyline of Hope's second ability applies only once
This is designed to be played with 1-3 players players and receive the next hero on the Path to Heros
The deck has three solid board sweepers in Farewell , Fumigate , and Organic Extinction