Crashing Footfalls is a great way to win the game, and the Rhynos deck is sweet and strong: you play a very good tempo game using a ton of free spells such as Fury and Endurance, and then you cascade and gain back the advantage
To resolve Sheoldred's enters-the-battlefield ability in a multiplayer game, the next opponent in turn order (or, if it's an opponent's turn, the opponent whose turn it is) chooses a creature they control to sacrifice
That's exactly what I envision happened with Skycoach Conductor, a 2/3 Bird Pilot with Flying and Vigilance
Some formats, most notably Commander, dont allow a sideboard
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