Nexus of Becoming

The trick is that this reads its own draw before deciding what to build. At the beginning of combat on your turn, it refills your hand and then hands you the option to convert whatever you just found (or already held) into a token: a 3/3 Golem stapled to the exiled card's other abilities. That sequencing matters, because the draw feeds the exile, so a hand emptying out one turn can be back in business the next, with the freshly-drawn artifact or creature going straight onto the battlefield as a body that carries its own text along for the ride. The Golem clause is the floor-setter here; it guarantees a fighting stat line even on a token copied from a noncreature artifact, which quietly turns support pieces into blockers and attackers you would not otherwise get. Be careful, though: the token is a true copy with added types, so it inherits every supertype the original had. Copy a Legendary card and you are subject to the legend rule like any other copy. What makes this a genuine engine rather than a one-shot is that the whole loop repeats with no further investment: no tap, no sacrifice, no mana. It sits on the board and manufactures a new game piece each turn it survives to your combat, the kind of colorless, deck-agnostic value that goes wherever six mana and a long game are on offer.