If the discarded card has in its mana cost, X is 0 for the purpose of determining its mana value.
(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Lightning — This creature deals 3 damage to each of up to two target creatures.
II — Ice — Up to three target creatures can't block this turn.
III — Fire — Discard a card, then draw two cards. When you discard a card this way, this creature deals damage equal to that card's mana value to each opponent.
in its mana cost, X is 0 for the purpose of determining its mana value.