Probably Mox Amber. The card just doesn't seem that good to me, but I haven't played any Mizzix. Is it better than I assume it is?
November 2, 2018 2:23 p.m.
I'm a bit inexperienced, but as far as Mox Amber goes, it can be an invaluable source of mana since it costs nothing to play. However, since you've already got Sol Ring and Thought Vessel that don't require your commander to be in play, it might be a good idea to keep Guttersnipe since it can be a pretty solid source of damage. But, if I recall correctly copies of spells just go on the stack and aren't "cast" so you could probably do without gutter boi.