2016-11-08 : Causing an opponent to lose the game after you've announced that you're casting a spell with undaunted and determined its total cost won't cause you to have to pay more mana.

2016-11-08 : Effects that reduce what you pay to cast a spell don't affect its mana value.

2016-11-08 : If each target is illegal as Seeds of Renewal resolves, Seeds of Renewal doesn't resolve and is put into its owner's graveyard. It's not exiled.

2016-11-08 : If one target becomes illegal before Seeds of Renewal resolves, you'll still return the legal target from your graveyard to your hand.