Seed of Vyssaffia:

Whenever the wielder of this artifact naturally rolls a 1 casting a spell, this artifact gains a charge. At the start of a war session, the wielder of this artifact may spend a charge to choose growth or decay. Growth - The wielder may cast entangle once per battle without paying its mana cost. They can not magical malfunction during this process. Decay - You may cast March of the dead for 3 mana cheaper to a minimum of 0. They can not magical malfunction during this process. Charges: 1/1