(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza s Saga gains {T}: Add {C}.
II — Urza s Saga gains {2}, {T}: Create a 0 0 colorless Construct artifact creature token with This creature gets +1 +1 for each artifact you control.
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.