Oil-Gorger Troll

Five mana buys a 3/4 and three life no matter what deck you slot it into: that half of the card asks for nothing and delivers a serviceable body with a lifegain buffer stapled on. The second clause is where it starts negotiating. Draw a card, but only if you already control a permanent carrying an oil counter when the troll lands. That conditional cantrip is the whole argument. Green has always paid for its card advantage in cardboard, preferring big bodies and combat math to raw refills, and this smuggles a card into a transaction green is already happy to make, using a counter type it does not natively produce as the price of admission. The bar barely clears the floor: any permanent, any oil counter satisfies it, so the troll does not demand a dedicated build so much as a nod to one. Miss the counter and you have a lifegain blocker; hit it and you have a lifegain blocker that replaced itself. This is not a repeatable engine but a single entry trigger, and that is what keeps the payout honest: it fires once, on the way in, so the deckbuilding question is entirely whether the oil is already on the board when the creature resolves. The gap between the floor and the ceiling, decided by one counter you may or may not control, is what lifts the rate above a plain green fatty's.