Wizards of the Coast
We've seen crazy combos go off in Magic: The Gathering Online streams before but seeing it happen on Turn-1 is pretty rare. You have to be extremely lucky to have all the cards to pull it off but your chances of storming off in Legacy is definitely way higher compared to Modern and Standard. Need proof? Check out the clip at the 42:49 mark below from Channelfireball:
In this video, Italian Magic: The Gathering professional player Andrea Mengucci shows us the power of Mardu in the Legacy format in Magic Online, and one of his opponents was able to pull off a turn-one kill using a bunch of spells like Lotus Petal, Desperate Ritual, Bonus Round, Rite of Flame, Burning Wish, Hazoret's Undying Fury, Seething Song, Ruby Medalion, Manamorphose, Reforge the Soul before finishing it off with Tendrils of Agony. Thanks to the Storm effect and the previous spells he played before Tendrils, he was able to deal a lethal blow to Mengucci who sounded stunned to see his opponent's combo go off.
It's fun to watch Mengucci's opponent play most of the cards in his deck before unleashing Tendrils of Agony.