Urza, Lord Protector [The Brothers' War]

Urza, Lord Protector [The Brothers' War]Set: The Brothers' War Type: Legendary Creature Human Artificer Rarity: Mythic Cost: {1}{W}{U} 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.

transform it and X Hyper Drivers you control into this

and a tragic tale

(Exile a creature card from your graveyard and pay its mana cost: Put a number of +1/+1 counters equal to that card's power on target creature

Whenever you cast an instant or sorcery spell that targets a creature you control

Set: Phyrexia: All Will Be One Type: Legendary Creature — Phyrexian Praetor Rarity: Mythic Cost: {4}{W} Vigilance

Set: EX: Hidden Legends Type: Fighting Rarity: Promo Retreat cost: Colorless

destroy Herald of Protection and close the combat chain

Whenever an artifact an opponent controls is put into a graveyard from the battlefield

Set: Phyrexia: All Will Be One Type: Artifact Rarity: Mythic Cost: {2}{U} Planeswalkers you control have “[0]: Proliferate” and “[-12]: Take an extra turn after this one

Set: The Brothers' War Retro Artifacts Type: Artifact Rarity: Mythic Cost: {4} {5}

defying Elesh Norn's commands

but I believe a more mundane power source might suffice