Rider System Core

{t}: Add {w}{u}{b}{r}{g}. Until the end of your next turn, you don’t lose unspent mana as steps and phases end.

Spend this mana only to cast legendary spells, activate abilities of legendary permanents, or cast Rider spells.

Whenever you spend three or more colors of mana
to cast a legendary spell, gain 1 life and scry 1.