Saheeli's Lattice // Mastercraft Raptor

Two mana buys a rummaging artifact that discards a card to draw two, refilling your hand while parking a craft target on the battlefield. That artifact does nothing further until you feed it: crafting for exiles one or more Dinosaurs from the battlefield or graveyard and flips the whole thing into Mastercraft Raptor, a body with power equal to everything you consumed. It is a finisher with no printed number, its ceiling set by the fodder you gathered rather than stamped on the card. The counterweight is timing: craft happens only as a sorcery, so you cannot ambush a blocker or spring a combat trick with it. The play has to be assembled on your own turn and telegraphed a step ahead, which hands the opponent a window to break up the setup before the raptor lands. Because the graveyard clause accepts dead Dinosaur cards alongside living ones, spent attackers and creatures killed in earlier combat become deferred size instead of wasted resources, so a board wipe you weathered still translates into raw material. Front to back, it reads as a two-stage engine: colorless card selection early, then a payoff scaled precisely to how much you were willing to sacrifice to summon it.