Sauron, the Lidless Eye

The enters trigger is where the design does its real work: an Act of Treason stapled to a 4/4 body, untapping the stolen creature and handing it haste so a defensive blocker becomes an extra attacker on the turn you drop the legend. On its own the theft is temporary, and that is the honest read of the card in a vacuum. But it is built to be paired: because the borrowed creature stays yours through your whole turn, any outside sacrifice outlet you supply turns a rental into a permanent removal spell, converting the biggest thing across the table into fuel before it ever goes home. The pump activation deepens the same axis rather than opening a new one, pushing +2/+0 across a board you have just widened by one and draining each opponent for two, which turns what looks like a mana sink into a way to close a stalled turn. Black-red has a long line of cards that borrow an opponent's board and cash it in, and this compresses the "steal it, swing with it" half into a single five-drop while leaving the "eat it" half to the deck around it: the card supplies the theft and the reach, and asks you to bring the outlet that makes the theft stick. The flavor tracks the mechanics precisely: the Dark Lord bending others to his will and turning their strength against them is exactly what the enters trigger enacts.