Artifact, instant, and sorcery spells you cast cost {1} less to cast. {7}: If you both own and control Urza, Lord Protector and an artifact named The Mightstone and Weakstone, exile them, then meld them into Urza, Planeswalker. Activate only as a sorcery.

Worn Powerstone enters the battlefield tapped. {T}: Add {C}{C}.

{T}, Tap X untapped artifacts you control: Look at the top X cards of your library. Put one of those cards into your hand and the rest into your graveyard. Partner (You can have two commanders if both have partner.)

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.) I — Scry 4, then you may reveal the top card of your library. If a planeswalker card is revealed this way, put it into your hand. II — You may put a planeswalker card with mana value 6 or less from your hand onto the battlefield. III — You may activate the loyalty abilities of planeswalkers you control twice this turn rather than only once.

{T}: Add {C}. If you control an Urza's Mine and an Urza's Power-Plant, add {C}{C}{C} instead.

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.) Exile all nonland permanents that aren't legendary.