What if Magic gives the second player a Lotus Petal, similar to what Hearthstone does?
There are already decks that win on turn one, giving one extra mana on that turn enables these decks to be more reliable.

One example of a deck that wins turn one, and already wants to be on the draw, is Flash Hulk. While Flash has been banned in legacy and restricted in vintage, the combo only needs two mana, one of it blue, to win turn 1. This two mana is usually accomplished with Gemstone Caverns, Elvish Spirit Guide or Simian Spirit Guide and the land drop for the turn, usually an Island. Adding one free mana would mean you no longer need one of those three cards, just Flash and Protean Hulk and your land for turn in the opening hand.

Flash is used to put Protean Hulk into play, which must be sacrificed since you can't pay the 4 generic mana required by Flash (creature's CMC-2), triggering Protean Hulk's death effect. That effect could search for many things, 4 Disciple of the Vault and X cost artifact creatures like Phyrexian Marauder and Shifting Wall, using the 0 toughness artifact creatures dying to trigger the Disciples, or 4 Virulent Sliver and a Heart Sliver to swing 5 poisonous 4 hasted creatures turn 1, doing double the lethal poison count.