For a while, I thought it was just a misinterpretation of the description, but it still doesn't make much sense. Taking the Wall-nut as an example, the "Parting Gift" description explicitly states: "Generates a cosmic cloud when this plant is MERGED or DEFEATED, increasing attack speed. The effect lasts 20 seconds."
However, if there is a plant on the field (with the "Parting Gift" trait) and I merge it directly with another plant on the field, the cosmic cloud simply stays behind.
Furthermore, if another plant is merged with a Wall-nut (or any plant with the same boost), the resulting plant doesn't gain the boost, nor does the cloud appear on the lawn; the same thing happens if I place a plant with this boost directly from the selection of five plants at the bottom.
