Costing three ink, Winnie the Pooh, Having a Think has some pretty good stats and decent lore retrieval
For Clerics, Aerith Gainsborough and Rosa, Resolute White Mage are the obvious choices
At the time, Jon was quietly regarded as the best player to have never Top 8ed a Pro Tour by players in the know
Its effect deals with +1/+1 counters, which see a lot of use in the format
Here is an example of a pretty all-in Emrakul, the Promised End decklist: Creatures (12) 1 Dragonlord Silumgar 1 Den Protector 1 Nissa, Vastwood Seer 3 Hangarback Walker 4 Deathcap Cultivator 2 Emrakul, the Promised End Planeswalkers (4) Lands (23) Spells (21) Obviously Nahiri, the Harbinger is a natural fit for Emrakul, the Promised End, and Patrick Chapin wrote last week about a bunch of different versions of Emrakul, the Promised End decks, many of which included the Boros planeswalker
Fecund Greenshell Getting the anthem off Fecund Greenshell wont be a problem in Commander, though other Constructed formats might find amassing 10 lands tricky