Clockwork Servant

The clearest teaching example of adamant's bargain: pay full color-purity on your mana, get a small reward. Here the reward is a card, and the price is aiming three same-colored pips at a body that carries no color identity of its own. That inversion is the whole point of the mechanic, which asks you to lean into a monocolor or heavily color-committed manabase rather than the greedy fixing that artifacts usually enable. A colorless creature that pays you specifically for casting it with colored mana is deliberate friction: it sits anywhere as a 2/3, but only replaces itself when the surrounding mana cooperates. The trigger is a conditional enters check, so it is a single-shot on the way in rather than a repeating engine, and the check runs each time the creature is cast: bounce it and recast it with three mana of one color, and the draw comes again. What it does not do is grind by itself; nothing here loops without outside help. That earn-it structure is what keeps the rate reasonable: a body plus a cantrip when you built to satisfy the condition, a slightly overcosted body when you did not. As gnome-tribe artifact material it slots into whatever wants cheap colorless bodies, but the design outclasses the payoff. It exists to demonstrate how a keyword can reward committing to a single color without ever printing a color pip on the card itself.