Heartbeat of Spring/Mana Flare feel like almost pure combo cards to me. Either playing them the turn you combo off or the turn before daring your opponent to beat you in one turn or lose.
One non-combo build this might be viable in is something discard heavy. If your opponent has nothing to play, it matters less that they have a million mana. Still feels dicey though since an Emrakul top deck still probably just wins.
These are cards I don't think are cube friendly. I have them in my retro list but have no confidence they are actually draftable outside storm (and even that deck just feels really ambitious most of the time).
One non-combo build this might be viable in is something discard heavy. If your opponent has nothing to play, it matters less that they have a million mana. Still feels dicey though since an Emrakul top deck still probably just wins.
These are cards I don't think are cube friendly. I have them in my retro list but have no confidence they are actually draftable outside storm (and even that deck just feels really ambitious most of the time).