You need to have a nontoken creature with Haste in play, as well as another creature to attach Breath of Fury to
At the baseline, you have an overstatted 1 drop with deathtouch
Emiel is most often used for its first ability, the flicker effect
Channel and Sneak Attack don't have similar rules text, for example, but they overlap in their ability to do broken things with big colorless creatures, so you might pick up a Sneak Attack to support your early-pick Channel, and then prioritize the legendary Eldrazi creatures, Blightsteel Colossus, and Sundering Titan over a card like Karn Liberated, which only works with the Channel plan
The key was figuring out how to get the creature through
According to the user nocash168 on Reddit, the Keldeo print for the Crown Zenith expansion is an absolute stunner and super cheap