Kotis, the Fangkeeper

The cascade-style payoff attaches itself to a combat trigger, which changes everything about how you use it. Cascade fires when you cast; this fires when Kotis connects, and the exiled cards it lets you cast free are gated by the exact damage dealt. That coupling turns a fragile 2/1 into a build-around: the reward scales precisely with how much you can pump the body before combat damage resolves, so a single connecting hit pumped to five is a five-mana-value spell (or a fistful of cheaper ones) off the top of an opponent's deck, cast for nothing. The indestructibility is what makes the plan repeatable rather than a one-time gamble; it survives blocks and most sweepers, so the trigger is a threat every turn rather than a coin flip you make once. The design tension sits in the value being capped by your own damage output and drawn from the opponent's library, not yours, which means you are casting their spells, without paying their costs, on your terms. That is a fundamentally different resource axis from graveyard recursion or your own impulse draw: the card weaponizes an opponent's deck against them, and the more you widen the combat step, the wider the window into their library opens.