Stenn, Paranoid Partisan

Cost reduction stapled to a legendary body is usually a build-around's problem: the reducer dies to a stiff breeze, and the deck folds without it. This design answers that fragility with its own escape hatch. For two mana you name a card type (instants, artifacts, enchantments, sorceries, planeswalkers, or battles) and shave a generic mana off every spell of that type you cast; but the activated ability lets you pay to exile Stenn yourself, blinking it out of the way of targeted removal or a board wipe and returning it untapped, ready to pick a new type on the way back. That reentry is the real hook, because the type choice happens as Stenn enters. Blink it and you re-choose: the reducer pointed at instants this turn can come back naming artifacts to fire off a different half of your deck, or simply leave the battlefield entirely to dodge a destroy-target spell. Note the ceiling the reduction stops at generic: it cannot make a colored spell free, so it accelerates without breaking the mana-cost floor that keeps two-color tempo honest. The result is a discount engine that answers the usual objection to discount engines, which is that they are the first thing your opponent kills. Stenn simply asks to be killed while it is somewhere else.