Killian, Ink Duelist

The design pitch is targeting-as-a-color-pair. Orzhov has always leaned on point removal and single-target buffs; this legend takes that instinct and prices it, knocking two mana off anything you cast at a creature. That covers both directions of the axis: your removal gets cheaper, but so do your Auras and combat tricks targeting a creature. A two-mana discount on a two-color deck's targeted spells is aggressive enough that the body has to stay small to pay for it, and a 2/2 does. The lifelink-and-menace combination is the other half of the balancing act: the discount rewards you for pointing spells at creatures, and a warlock who is hard to block and drains life every time it connects wants exactly the pump-and-remove interaction the cost reduction subsidizes. What keeps the reduction honest is the target restriction: it only touches spells aimed at a creature, so it does nothing for your sweepers, your discard, or your artifact removal. The effect is narrow by design, and that narrowness is what lets it be this generous. Cost reduction on a discrete category of spells is a design lever that rewards building the entire deck around one verb, and here the verb is "target a creature." Nothing about the rate is subtle; the whole card is an argument that a deck willing to commit to pointing spells at things should get paid for it.