Multani's Acolyte

Echo and a cantrip on the same Elf is a tidy bit of cost-smoothing that the rate hides in plain sight: you pay GG to cast it, draw a card, and then face a second GG bill on your next upkeep or lose the body. The design treats the draw as the thing you actually bought, with the 2/1 as a deposit you can walk away from. If you intend to keep the Elf, you have effectively paid four green mana split across two turns for a 2/1 and a card. If you do not, you have paid GG for a creature that blocks once, replaces itself, and dies on schedule without you spending another mana. Echo was the Urza-block mechanic built precisely for this kind of deferred-cost bargaining, and pairing it with a draw-on-entry trigger makes the up-front cast easy to justify regardless of which half of the deal you eventually take. The friction is the timing of the echo trigger: it goes on the stack at the beginning of your upkeep and demands payment then, and left alone it cannot stick around uncontested past that first window. What looks like an undercosted cantrip body is really a question the card asks once per game, with the green mana you have available on the following turn supplying the answer.