This is a difficult haiku constraint because ALLOY is technical, abstract, and not naturally image-bearing unless the poem builds the right field for it. Haiku tends to want something immediate and sensory, while a word like this can sit there like a concept unless it is attached to action, material, or analogy. Mark’s “RAISE corn, PLANT beans, squash / CLOAK weeds, ALLOW beans to climb / Nature’s wise ALLOY” is a good example of solving that well: the constraint words are absorbed into a coherent growing system, so ALLOY reads as mixture and mutual design rather than as a vocabulary requirement. Across the set, the stronger poems either make the target word part of a process of discovery or turn it into a meaningful metaphor for combination.